Geometry Standards
MA19.GDA,Geometry with Data Analysis
MA19.GDA.NQ Number and Quantity
MA19.GDA.NQ.A
Together, irrational numbers and rational numbers complete the real number system, representing all points on the number line, while there exist numbers beyond the real numbers called complex numbers.
MA19.GDA.NQ.B
Quantitative reasoning includes and mathematical modeling requires attention to units of measurement.
MA19.GDA.AF Algebra and Functions
MA19.GDA.AF.1 Focus 1: Algebra
MA19.GDA.AF.1.A
The structure of an equation or inequality (including, but not limited to, one-variable linear and quadratic equations, inequalities, and systems of linear equations in two variables) can be purposefully analyzed (with and without technology) to determine an efficient strategy to find a solution, if one exists, and then to justify the solution.
MA19.GDA.AF.1.B
Expressions, equations, and inequalities can be used to analyze and make predictions, both within mathematics and as mathematics is applied in different contexts - in particular, contexts that arise in relation to linear, quadratic, and exponential situations.
MA19.GDA.AF.2,Focus 2: Connecting Algebra to Functions
MA19.GDA.AF.2.A
Graphs can be used to obtain exact or approximate solutions of equations, inequalities, and systems of equations and inequalities--including systems of linear equations in two variables and systems of linear and quadratic equations (given or obtained by using technology).
MA19.GDA.DA Data Analysis, Statistics, and Probability
MA19.GDA.DA.1,Focus 1: Quantitative Literacy
MA19.GDA.DA.1.A
Mathematical and statistical reasoning about data can be used to evaluate conclusions and assess risks. MA19.GDA.DA.2 Focus 2: Visualizing and Summarizing Data
MA19.GDA.DA.2.A
Data arise from a context and come in two types: quantitative (continuous or discrete) and categorical. Technology can be used to ""clean"" and organize data, including very large data sets, into a useful and manageable structure -- a first step in any analysis of data
MA19.GDA.DA.2.B
Distributions of quantitative data (continuous or discrete) in one variable should be described in the context of the data with respect to what is typical (the shape, with appropriate measures of center and variability, including standard deviation) and what is not (outliers), and these characteristics can be used to compare two or more subgroups with respect to a variable.
MA19.GDA.DA.2.C
Scatter plots, including plots over time, can reveal patterns, trends, clusters, and gaps that are useful in analyzing the association between two contextual variables.
MA19.GDA.DA.2.D
Analyzing the association between two quantitative variables should involve statistical procedures, such as examining (with technology) the sum of squared deviations in fitting a linear model, analyzing residuals for patterns, generating a least-squares regression line and finding a correlation coefficient, and differentiating between correlation and causation.
MA19.GDA.GM,Geometry and Measurement
MA19.GDA.GM.1,Focus 1: Measurement
MA19.GDA.GM.1.A
Areas and volumes of figures can be computed by determining how the figure might be obtained from simpler figures by dissection and recombination.
MA19.GDA.GM.1.B
Constructing approximations of measurements with different tools, including technology, can support an understanding of measurement.
MA19.GDA.GM.1.C
When an object is the image of a known object under a similarity transformation, a length, area, or volume on the image can be computed by using proportional relationships.
MA19.GDA.GM.2,Focus 2: Transformations
MA19.GDA.GM.2.A
Applying geometric transformations to figures provides opportunities for describing the attributes of the figures preserved by the transformation and for describing symmetries by examining when a figure can be mapped onto itself.
MA19.GDA.GM.2.B
Showing that two figures are congruent involves showing that there is a rigid motion (translation, rotation, reflection, or glide reflection) or, equivalently, a sequence of rigid motions that maps one figure to the other.
MA19.GDA.GM.2.C
Showing that two figures are similar involves finding a similarity transformation (dilation or composite of a dilation with a rigid motion) or, equivalently, a sequence of similarity transformations that maps one figure onto the other.
MA19.GDA.GM.3Focus 3: Geometric Arguments, Reasoning, and Proof
MA19.GDA.GM.3.A
Using technology to construct and explore figures with constraints provides an opportunity to explore the independence and dependence of assumptions and conjectures.
MA19.GDA.GM.3.B
Proof is the means by which we demonstrate whether a statement is true or false mathematically, and proofs can be communicated in a variety of ways (e.g., two-column, paragraph).
MA19.GDA.GM.3.C
Proofs of theorems can sometimes be made with transformations, coordinates, or algebra; all approaches can be useful, and in some cases one may provide a more accessible or understandable argument than another.
MA19.GDA.GM.4,Focus 4: Solving Applied Problems and Modeling in Geometry
MA19.GDA.GM.4.A
Recognizing congruence, similarity, symmetry, measurement opportunities, and other geometric ideas, including right triangle trigonometry, in real-world contexts provides a means of building understanding of these concepts and is a powerful tool for solving problems related to the physical world in which we live.
MA19.GDA.GM.4.B
Experiencing the mathematical modeling cycle in problems involving geometric concepts, from the simplification of the real problem through the solving of the simplified problem, the interpretation of its solution, and the checking of the solution's feasibility, introduces geometric techniques, tools, and points of view that are valuable to problem-solving.
MA19.GDA.1
Extend understanding of irrational and rational numbers by rewriting expressions involving radicals, including addition, subtraction, multiplication, and division, in order to recognize geometric patterns.
Teacher Vocabulary
- Geometric patterns
- Irrational numbers
- Rational numbers
Knowledge
Students know:
- Order of operations, algebraic properties, and number sense.
- Computation with whole numbers and integers.
- Radicals.
- Rational and irrational numbers.
- How to measure the length and find the perimeter and area of rectangles and squares.
- Volume and capacity.
- Pythagorean theorem.
Skills
Students are able to:
- Simplify radicals and justify simplification of radicals using visual representations.
- Use the operations of addition, subtraction, division, and multiplication, with radicals.
- Demonstrate an understanding of radicals as they apply to problems involving squares, perfect squares, and square roots (e.g., the Pythagorean theorem, circle geometry, volume, and area).
- Rewrite radical expressions.
Understanding
Students understand that:
- Rewriting radical expressions of rational and irrational numbers can help in recognizing geometric patterns.
MA19.GDA.2
MA19.GDA.2a
Choose and interpret units consistently in formulas.
MA19.GDA.2b
Choose and interpret the scale and the origin in graphs and data displays.
MA19.GDA.2c
Define appropriate quantities for the purpose of descriptive modeling.
MA19.GDA.2d
Choose a level of accuracy appropriate to limitations of measurements when reporting quantities.
MA19.GDA.DA.2.E
Data analysis techniques can be used to develop models of contextual situations and to generate and evaluate possible solutions to real problems involving those contexts.
Teacher Vocabulary
- Accuracy
- Area
- Consistency
- Descriptive modeling
- Dimensional analysis
- Direct measurement
- Formulas
- Identify
- Interpret
- Justify
- Margin of error
- Perimeter
- Precise
- Quantities
- Scale
- Scales
- Units
- Volume
Knowledge
Students know:
- Techniques for dimensional analysis,
- Uses of technology in producing graphs of data.
- Criteria for selecting different displays for data (e.g., knowing how to select the window on a graphing calculator to be able to see the important parts of the graph.)
- Descriptive models.
- Attributes of measurements including precision and accuracy and techniques for determining each.
Skills
Students are able to:
- Choose the appropriate known conversions to perform dimensional analysis to convert units.
- Correctly use graphing window and other technology features to precisely determine features of interest in a graph.
- Determine when a descriptive model accurately portrays the phenomenon it was chosen to model.
- Justify their selection of model and choice of quantities in the context of the situation modeled and critique the arguments of others concerning the same situation.
- Determine and distinguish the accuracy and precision of measurements.
Understanding
Students understand that:
- The relationships of units to each other and how using a chain of conversions allows one to reach a desired unit or rate.
- Different models reveal different features of the phenomenon that is being modeled.
- Calculations involving measurements cannot be more accurate than the least precise measurement used in the calculation.
- The margin of error in a measurement, often expressed as a tolerance limit, varies according to the measurement, tool used, and problem context.
MA19.GDA.3
Teacher Vocabulary
- Function rules
- Linear equations
- System of equations
- Vertices
Knowledge
Students know:
- Substitution, elimination, and graphing methods to solve simultaneous linear equations.
Skills
Students are able to:
- Find the coordinates of the vertices of a polygon given a set of lines and their equations by setting their function rules equal and solving or by using their graph.
Understanding
Students understand that:
- Given the equations to a set of lines you can find the coordinates of the vertices of a polygon by setting their function rules equal and solving or by using their graph.
MA19.GDA.4
Teacher Vocabulary
- Constant
- Literal equations
- Variable
Knowledge
Students know:
- Properties of equality and inequality.
Skills
Students are able to:
- Accurately rearrange equations or inequalities to produce equivalent forms for use in resolving situations of interest.
Understanding
Students understand that:
- The structure of mathematics allows for the procedures used in working with equations to also be valid when rearranging formulas.
- The isolated variable in a formula is not always the unknown and rearranging the formula allows for sense-making in problem solving.
MA19.GDA.5
Teacher Vocabulary
- Graphically finite solutions
- Infinite solutions
Knowledge
Students know:
- Appropriate methods to find ordered pairs that satisfy an equation.
- Techniques to graph the collection of ordered pairs to form a line.
Skills
Students are able to:
- Accurately find ordered pairs that satisfy the equation.
- Accurately graph the ordered pairs and form a line.
Understanding
Students understand that:
- An equation in two variables has an infinite number of solutions (ordered pairs that make the equation true), and those solutions can be represented by the graph of a line (or curve), depending on the type of equation.
MA19.GDA.6
Derive the equation of a circle of given center and radius using the Pythagorean Theorem.
MA19.GDA.6a
Given the endpoints of the diameter of a circle, use the midpoint formula to find its center and then use the Pythagorean Theorem to find its equation.
MA19.GDA.6b
Teacher Vocabulary
- Pythagorean Theorem
- Radius
- Translation
Knowledge
Students know:
- Key features of a circle.
- The Pythagorean Theorem, midpoint formula, and distance formula.
Skills
Students are able to:
- Create a right triangle in a circle using the horizontal and vertical shifts from the center as the legs and the radius of the circle as the hypotenuse.
- Write the equation of the circle in standard form when given the endpoints of the diameter of a circle, using the midpoint formula to find the circle's center, and then use the Pythagorean Theorem to find the equation of the circle.
- Find the distance between two points when using the Pythagorean Theorem and use that process to create the distance formula.
Understanding
Students understand that:
- Circles represent a fixed distance in all directions in a plane from a given point, and a right triangle may be created to show the relationship of the horizontal and vertical shift to the distance.
- Circles written in standard form are useful for recognizing the center and radius of a circle.
- The distance formula and Pythagorean Theorem can both be used to find length measurements of segments (or sides of a geometric figure).
MA19.GDA.7
Use mathematical and statistical reasoning with quantitative data, both univariate data (set of values) and bivariate data (set of pairs of values) that suggest a linear association, in order to draw conclusions and assess risk.
Teacher Vocabulary
- Bar graphs
- Bivariate data
- Histograms
- Linear association
- Linear model
- Mathematical reasoning
- Mean
- Median
- Mode
- Pie graphs
- Quantitative data
- Scatter plots
- Slope
- Standard deviation
- Statistical reasoning
- Univariate data
Knowledge
Students know:
- Patterns found on scatter plots of bivariate data.
- Strategies for determining slope and intercepts of a linear model.
- Strategies for informally fitting straight lines to bivariate data with a linear relationship.
- Methods for finding the distance between two points on a coordinate plane and between a point and a line.
Skills
Students are able to:
- Construct a scatter plot to represent a set of bivariate data.
- Use mathematical vocabulary to describe and interpret patterns in bivariate data.
- Use logical reasoning and appropriate strategies to draw a straight line to fit data that suggests a linear association.
- Use mathematical vocabulary, logical reasoning, and the closeness of data points to a line to judge the fit of the line to the data.
- Find a central value using mean, median, and mode.
- Find how spread out the univariate data is using the range, quartiles, and standard deviation.
- Make plots like bar graphs, pie charts, and histograms.
Understanding
Students understand that:
- Using different representations and descriptors of a data set can be useful in seeing important features of the situation being investigated.
- When visual examination of a scatter plot suggests a linear association in the data, fitting a straight line to the data can aid in interpretation and prediction.
- Modeling bivariate data with scatter plots and fitting a straight line to the data can aid in the interpretation of the data and predictions about unobserved data.
- A set of data collected to answer a statistical question has a distribution that can be described by its center, spread, and overall shape.
- Using different representations and descriptors of a data set can be useful in seeing important features of the situation being investigated.
- Statistical measures of center and variability that describe data sets can be used to compare data sets and answer questions.
MA19.GDA.8
Use technology to organize data, including very large data sets, into a useful and manageable structure.
Teacher Vocabulary
- Categorical
- Continuous data
- Curve of best fit
- Discrete data
- Line of best fit
- Quantitative
- Scatter plot
Knowledge
Students know:
- How to use technology to create graphical models of data in scatterplots or frequency distributions.
- How to use technology to graph scatter plots given a set of data and estimate the equation of best fit.
- How to distinguish between independent and dependent variables.
Skills
Students are able to:
- Recognize patterns, trends, clusters, and gaps in the organized data.
Understanding
Students understand that:
- Sets of data can be organized and displayed in a variety of ways each of which provides unique perspectives of the data set.
- Data displays help in conceptualizing ideas and in solving problems.
MA19.GDA.9
Represent the distribution of univariate quantitative data with plots on the real number line, choosing a format (dot plot, histogram, or box plot) most appropriate to the data set, and represent the distribution of bivariate quantitative data with a scatter plot. **Extend from simple cases by hand to more complex cases involving large data sets using technology.**
Teacher Vocabulary
- Bivariate data
- Box plots
- Dot plots
- Histograms
- Scatter plots
- Univariate data
Knowledge
Students know:
- Techniques for constructing dot plots, histograms, scatter plots, and box plots from a set of data.
Skills
Students are able to:
- Choose from among data displays (dot plots, histograms, box plots, scatter plots) to convey significant features of data.
- Accurately construct dot plots, histograms, and box plots.
- Accurately construct scatter plots using technology to organize and analyze the data.
Understanding
Students understand that:
- Sets of data can be organized and displayed in a variety of ways, each of which provides unique perspectives of the data set.
- Data displays help in conceptualizing ideas and in solving problems.
MA19.GDA.10
Use statistics appropriate to the shape of the data distribution to compare and contrast two or more data sets, utilizing the mean and median for center and the interquartile range and standard deviation for variability.
MA19.GDA.10a
Explain how standard deviation develops from mean absolute deviation.
MA19.GDA.10b
Calculate the standard deviation for a data set, using technology where appropriate.
Teacher Vocabulary
- Absolute mean deviation
- Center
- Interquartile range
- Mean
- Median
- Spread
- Standard deviation
Knowledge
Students know:
- Techniques to calculate the center and spread of data sets.
- Techniques to calculate the mean absolute deviation and standard deviation.
- Methods to compare data sets based on measures of center (median, mean) and spread (interquartile range and standard deviation) of the data sets.
Skills
Students are able to:
- Accurately find the center (median and mean) and spread (interquartile range and standard deviation) of data sets.
- Present viable arguments and critique arguments of others from the comparison of the center and spread of multiple data sets.
- Explain their reasoning on how standard deviation develops from the mean absolute deviation.
Understanding
Students understand that:
- Multiple data sets can be compared by making observations about the center and spread of the data.
- The center and spread of multiple data sets are used to justify comparisons of the data.
- Both the mean and the median are used to calculate the mean absolute and standard deviations.
MA19.GDA.11
Interpret differences in shape, center, and spread in the context of data sets, accounting for possible effects of extreme data points (outliers) on mean and standard deviation.
Teacher Vocabulary
- Center
- Mean
- Outliers
- Shape
- Spread
- Standard deviation
Knowledge
Students know:
- Techniques to calculate the center and spread of data sets.
- Methods to compare attributes (e.g. shape, median, mean, interquartile range, and standard deviation) of the data sets.
- Methods to identify outliers.
Skills
Students are able to:
- Accurately identify differences in shape, center, and spread when comparing two or more data sets.
- Accurately identify outliers for the mean and standard deviation.
- Explain, with justification, why there are differences in the shape, center, and spread of data sets.
Understanding
Students understand that:
- Differences in the shape, center, and spread of data sets can result from various causes, including outliers and clustering.
MA19.GDA.12
Represent data of two quantitative variables on a scatter plot, and describe how the variables are related.
Teacher Vocabulary
- Quantitative variables
- Residuals
- Scatter plot
Knowledge
Students know:
- Techniques for creating a scatter plot.
- Techniques for fitting linear functions to data.
- Methods for using residuals to judge the closeness of the fit of the linear function to the original data.
Skills
Students are able to:
- Accurately create a scatter plot of data.
- Make reasonable assessments on the fit of the function to the data by examining residuals.
- Accurately fit a function to data when there is evidence of a linear association.
- Use technology to find the least-squares line of best fit for two quantitative variables.
Understanding
Students understand that:
- Functions are used to create equations representative of ordered pairs of data.
- Residuals may be examined to analyze how well a function fits the data.
- When a linear association is suggested, a linear function can be fit to the scatter plot to aid in modeling the relationship.
MA19.GDA.12a Find a linear function for a scatter plot that suggests a linear association and informally assess its fit by plotting and analyzing residuals, including the squares of the residuals, in order to improve its fit. MA19.GDA.12b Use technology to find the least-squares line of best fit for two quantitative variables.
MA19.GDA.13
Compute (using technology) and interpret the correlation coefficient of a linear relationship.
Teacher Vocabulary
- Correlation coefficient
- Interpret
- Linear relationship
Knowledge
Students know:
- Techniques for creating a scatter plot using technology.
- Techniques for fitting linear functions to data.
- Accurately fit a function to data when there is evidence of a linear association.
Skills
Students are able to:
- Use technology to graph different data sets.
- Use the correlation coefficient to assess the strength and direction of the relationship between two data sets.
Understanding
Students understand that:
- Using technology to graph some data and look at the regression line that technology can generate for a scatter plot.
MA19.GDA.14
Distinguish between correlation and causation.
Teacher Vocabulary
- Causation
- Correlation
Knowledge
Students know:
- How to read and analyze scatter plots.
- Scatter plots can be used to look for trends and to find positive and negative correlations.
- The key differences between correlation and causation.
Skills
Students are able to:
- Distinguish between correlation and causation.
Understanding
Students understand that:
- Correlation does not imply causation; just because two variables are related does not mean one causes the other.
MA19.GDA.15
Evaluate possible solutions to real-life problems by developing linear models of contextual situations and using them to predict unknown values.
MA19.GDA.15a
Use the linear model to solve problems in the context of the given data.
MA19.GDA.15b
Interpret the slope (rate of change) and the intercept (constant term) of a linear model in the context of the given data.
Teacher Vocabulary
- Constant
- Horizontal lines
- Intercepts
- Ordered pairs
- Quantitative variables
- Rate of change
- Residuals
- Scatter plot
- Slope
- Vertical lines
Knowledge
Students know:
- Techniques for creating a scatter plot.
- Techniques for fitting a linear function to a scatter plot.
- Methods to find the slope and intercept of a linear function.
- Techniques for fitting various functions (linear, quadratic, exponential) to data.
- Methods for using residuals to judge the closeness of the fit of the function to the original data.
Skills
Students are able to:
- Accurately create a scatter plot of data.
- Correctly choose a function to fit the scatter plot.
- Make reasonable assessments on the fit of the function to the data by examining residuals.
- Accurately fit a linear function to data when there is evidence of a linear association.
- Accurately fit linear functions to scatter plots.
- Correctly find the slope and intercept of linear functions.
- Justify and explain the relevant connections slope and intercept of the linear function to the data.
Understanding
Students understand that:
- Functions are used to create equations representative of ordered pairs of data.
- Residuals may be examined to analyze how well a function fits the data.
- When a linear association is suggested, a linear function can be fit to the scatter plot to aid in modeling the relationship.
- Linear functions are used to model data that have a relationship that closely resembles a linear relationship.
- The slope and intercept of a linear function may be interpreted as the rate of change and the zero point (starting point).
MA19.GDA.16
Identify the shapes of two-dimensional cross-sections of three-dimensional objects, and identify three-dimensional objects generated by rotations of two-dimensional objects.
Teacher Vocabulary
- Cavalieri's Principle
- Circumference
- Cone
- Conjecture
- Cross-section
- Cylinder
- Dissection arguments
- Limits
- Parallelogram
- Pyramid
- Ratio
Knowledge
Students know:
- Techniques to find the area and perimeter of parallelograms.
- Techniques to find the area of circles or polygons.
Skills
Students are able to:
- Accurately decompose circles, cylinders, pyramids, and cones into other geometric shapes.
- Explain and justify how the formulas for the circumference of a circle, area of a circle, and volume of a cylinder, pyramid, and cone may be created from the use of other geometric shapes.
Understanding
Students understand that:
- Geometric shapes may be decomposed into other shapes which may be useful in creating formulas.
- Geometric shapes may be divided into an infinite number of smaller geometric shapes, and the combination of those shapes maintain the area and volume of the original shape.
MA19.GDA.17
Model and solve problems using surface area and volume of solids, including composite solids and solids with portions removed.
MA19.GDA.17a
Give an informal argument for the formulas for the surface area and volume of a sphere, cylinder, pyramid, and cone using dissection arguments, Cavalieri's Principle, and informal limit arguments.
MA19.GDA.17b
Apply geometric concepts to find missing dimensions to solve surface area or volume problems.
Teacher Vocabulary
- Cavalieri's Principle
- Circumference
- Cone
- Conjecture
- Cross-section
- Cylinder
- Dissection arguments
- Limits
- Parallelogram
- Pyramid
- Ratio
- Surface area
Knowledge
Students know:
- Techniques to find the area and perimeter of parallelograms.
- Techniques to find the area of circles or polygons.
Skills
Students are able to:
- Accurately decompose circles, spheres, cylinders, pyramids, and cones into other geometric shapes.
- Explain and justify how the formulas for surface area, and volume of a sphere, cylinder, pyramid, and cone may be created from the use of other geometric shapes.
Understanding
Students understand that:
- Geometric shapes may be decomposed into other shapes which may be useful in creating formulas.
- Geometric shapes may be divided into an infinite number of smaller geometric shapes, and the combination of those shapes maintain the area and volume of the original shape.
MA19.GDA.18
Given the coordinates of the vertices of a polygon, compute its perimeter and area using a variety of methods, including the distance formula and dynamic geometry software, and evaluate the accuracy of the results.
Teacher Vocabulary
- Accuracy
- Area
- Coordinates
- Distance formula
- Evaluate
- Perimeter
- Vertices
Knowledge
Students know:
- The distance formula and its applications.
- Techniques for coordinate graphing.
- Techniques for using geometric software for coordinate graphing and to find the perimeter and area.
Skills
Students are able to:
- Create geometric figures on a coordinate system from a contextual situation.
- Accurately find the perimeter of polygons and the area of polygons such as triangles and rectangles from the coordinates of the shapes.
- Explain and justify solutions in the original context of the situation.
Understanding
Students understand that:
- Contextual situations may be modeled in a Cartesian coordinate system.
- Coordinate modeling is frequently useful to visualize a situation and to aid in solving contextual problems.
MA19.GDA.19
Derive and apply the relationships between the lengths, perimeters, areas, and volumes of similar figures in relation to their scale factor.
Teacher Vocabulary
- Apply
- Derive
- Ratio of area
- Ratio of length
- Ratio of perimeter
- Ratio of volume
- Scale Factor
- Similar figures
Knowledge
Students know:
- Scale factors of similar figures.
- The ratio of lengths, perimeter, areas, and volumes of similar figures.
- Similar figures.
Skills
Students are able to:
- Find the scale factor of any given set of similar figures.
- Find the ratios of perimeter, area, and volume.
Understanding
Students understand that:
- Just as their corresponding sides are in the same proportion, perimeters and areas of similar polygons have a special relationship.
- The ratio of the perimeters is the same as the scale factor.
- If the scale factor of the sides of two similar polygons is m/n, then the ratio of the areas is (m/n) 2.
MA19.GDA.20
Derive and apply the formula for the length of an arc and the formula for the area of a sector.
Teacher Vocabulary
- Arc
- Arc length
- Area of sector
- Central angle
- Constant of proportionality
- Derive
- Dilation
- Radian measure
- Sector
- Similarity
Knowledge
Students know:
- Techniques to use dilations (including using dynamic geometry software) to create circles with arcs intercepted by the same central angles.
- Techniques to find arc length.
- Formulas for the area and circumference of a circle.
Skills
Students are able to:
- Reason from progressive examples using dynamic geometry software to form conjectures about relationships among arc length, central angles, and the radius.
- Use logical reasoning to justify (or deny) these conjectures and critique the reasoning presented by others.
- Interpret a sector as a portion of a circle, and use the ratio of the portion to the whole circle to create a formula for the area of a sector.
Understanding
Students understand that:
- Radians measure the ratio of the arc length to the radius for an intercepted arc.
- The ratio of the area of a sector to the area of a circle is proportional to the ratio of the central angle to a complete revolution.
MA19.GDA.21
Represent transformations and compositions of transformations in the plane (coordinate and otherwise) using tools such as tracing paper and geometry software.
MA19.GDA.21a
Describe transformations and compositions of transformations as functions that take points in the plane as inputs and give other points as outputs, using informal and formal notation.
MA19.GDA.21b
Compare transformations which preserve distance and angle measure to those that do not.
Teacher Vocabulary
- Clockwise
- Composition
- Counterclockwise
- Dilation
- Horizontal shrink
- Horizontal stretch
- Image
- Isometry
- Preimage
- Reflection
- Rotation
- Symmetry
- Transformation
- Translation
- Vertical shrink
- Vertical stretch
Knowledge
Students know:
- Characteristics of transformations (translations, rotations, reflections, and dilations).
- Methods for representing transformations.
- Characteristics of functions.
- Conventions of functions with mapping notation.
Skills
Students are able to:
- Accurately perform dilations, rotations, reflections, and translations on objects in the coordinate plane with and without technology.
- Communicate the results of performing transformations on objects and their corresponding coordinates in the coordinate plane, including when the transformation preserves distance and angle.
- Use the language and notation of functions as mappings to describe transformations.
Understanding
Students understand that:
- Mapping one point to another through a series of transformations can be recorded as a function.
- Some transformations (translations, rotations, and reflections) preserve distance and angle measure, and the image is then congruent to the pre-image, while dilations preserve angle but not distance, and the pre-image is similar to the image.
- Distortions, such as only a horizontal stretch, preserve neither.
MA19.GDA.22
Explore rotations, reflections, and translations using graph paper, tracing paper, and geometry software.
MA19.GDA.22a
Given a geometric figure and a rotation, reflection, or translation, draw the image of the transformed figure using graph paper, tracing paper, or geometry software.
MA19.GDA.22b
Specify a sequence of rotations, reflections, or translations that will carry a given figure onto another.
MA19.GDA.22c
Draw figures with different types of symmetries and describe their attributes.
Teacher Vocabulary
- Clockwise
- Composition
- Counterclockwise
- Dilation
- Horizontal shrink
- Horizontal stretch
- Image
- Isometry
- Mapping
- Parallelogram
- Preimage
- Rectangle
- Reflection
- Regular polygon
- Rotation
- Square
- Symmetry
- Transformation
- Translation
- Trapezoid
- Vertical shrink
- Vertical stretch
Knowledge
Students know:
- Characteristics of transformations (translations, rotations, reflections, and dilations).
- Techniques for producing images under transformations using graph paper, tracing paper, or geometry software.
- Characteristics of rectangles, parallelograms, trapezoids, and regular polygons.
Skills
Students are able to:
- Accurately perform dilations, rotations, reflections, and translations on objects in the coordinate plane with and without technology.
- Communicate the results of performing transformations on objects and their corresponding coordinates in the coordinate plane.
Understanding
Students understand that:
- Mapping one point to another through a series of transformations can be recorded as a function.
- Since translations, rotations and reflections preserve distance and angle measure, the image is then congruent.
- The same transformation may be produced using a variety of tools, but the geometric sequence of steps that describe the transformation is consistent.
MA19.GDA.23
Develop definitions of rotation, reflection, and translation in terms of angles, circles, perpendicular lines, parallel lines, and line segments.
Teacher Vocabulary
- Clockwise
- Composition
- Counterclockwise
- Dilation
- Image
- Isometry
- Preimage
- Reflection
- Rotation
- Transformation
- Translation
Knowledge
Students know:
- Characteristics of transformations (translations, rotations, reflections, and dilations).
- Properties of a mathematical definition, i.e., the smallest amount of information and properties that are enough to determine the concept. (Note: May not include all information related to the concept.)
Skills
Students are able to:
- Accurately perform rotations, reflections, and translations on objects with and without technology.
- Communicate the results of performing transformations on objects.
- Use known and developed definitions and logical connections to develop new definitions.
Understanding
Students understand that:
- Geometric definitions are developed from a few undefined notions by a logical sequence of connections that lead to a precise definition.
- A precise definition should allow for the inclusion of all examples of the concept and require the exclusion of all non-examples.
MA19.GDA.24
Define congruence of two figures in terms of rigid motions (a sequence of translations, rotations, and reflections); show that two figures are congruent by finding a sequence of rigid motions that maps one figure to the other.
Teacher Vocabulary
- Congruence
- Rigid motions
Knowledge
Students know:
- Characteristics of translations, rotations, and reflections, including the definition of congruence.
- Techniques for producing images under transformations using graph paper, tracing paper, compass, or geometry software.
- Geometric terminology (e.g., angles, circles, perpendicular lines, parallel lines, and line segments) which describes the series of steps necessary to produce a rotation, reflection, or translation.
Skills
Students are able to:
- Use geometric descriptions of rigid motions to accurately perform these transformations on objects.
- Communicate the results of performing transformations on objects.
Understanding
Students understand that:
- Any distance-preserving transformation is a combination of rotations, reflections, and translations.
- If a series of translations, rotations, and reflections can be described that transforms one object exactly to a second object, the objects are congruent.
MA19.GDA.25
Verify criteria for showing triangles are congruent using a sequence of rigid motions that map one triangle to another.
MA19.GDA.25a
Verify that two triangles are congruent if and only if corresponding pairs of sides and corresponding pairs of angles are congruent.
MA19.GDA.25b
Verify that two triangles are congruent if (but not only if) the following groups of corresponding parts are congruent: angle-side-angle (ASA), side-angle-side (SAS), side- side-side (SSS), and angle-angle-side (AAS).
Teacher Vocabulary
- Angle-side-angle (ASA)
- Corresponding sides and angles
- If and only if
- Rigid motions
- Side-angle-side (SAS)
- Side-side-side (SSS)
- Triangle congruence
Knowledge
Students know:
- Characteristics of translations, rotations, and reflections, including the definition of congruence.
- Techniques for producing images under transformations.
- Geometric terminology which describes the series of steps necessary to produce a rotation, reflection, or translation.
- Basic properties of rigid motions (that they preserve distance and angle).
- Methods for presenting logical reasoning using assumed understandings to justify subsequent results.
Skills
Students are able to:
- Use geometric descriptions of rigid motions to accurately perform these transformations on objects.
- Communicate the results of performing transformations on objects.
- Use logical reasoning to connect geometric ideas to justify other results.
- Perform rigid motions of geometric figures.
- Determine whether two plane figures are congruent by showing whether they coincide when superimposed by means of a sequence of rigid motions (translation, reflection, or rotation).
- Identify two triangles as congruent if the lengths of corresponding sides are equal (SSS criterion), if the lengths of two pairs of corresponding sides and the measures of the corresponding angles between them are equal (SAS criterion), or if two pairs of corresponding angles are congruent and the lengths of the corresponding sides between them are equal (ASA criterion).
- Apply the SSS, SAS, and ASA criteria to verify whether or not two triangles are congruent.
Understanding
Students understand that:
- If a series of translations, rotations, and reflections can be described that transforms one object exactly to a second object, the objects are congruent.
- It is beneficial to have minimal sets of requirements to justify geometric results (e.g., use ASA, SAS, or SSS instead of all sides and all angles for congruence).
MA19.GDA.26
Verify experimentally the properties of dilations given by a center and a scale factor.
MA19.GDA.26a
Verify that a dilation takes a line not passing through the center of the dilation to a parallel line, and leaves a line passing through the center unchanged.
MA19.GDA.26b
Verify that the dilation of a line segment is longer or shorter in the ratio given by the scale factor.,
Teacher Vocabulary
- Center
- Dilations
- Scale factor
Knowledge
Students know:
- Methods for finding the length of line segments (both in a coordinate plane and through measurement).
- Dilations may be performed on polygons by drawing lines through the center of dilation and each vertex of the polygon then marking off a line segment changed from the original by the scale factor.
Skills
Students are able to:
- Accurately create a new image from a center of dilation, a scale factor, and an image.
- Accurately find the length of line segments and ratios of line segments.
- Communicate with logical reasoning a conjecture of generalization from experimental results.
Understanding
Students understand that:
- A dilation uses a center point and line segments through vertex points to create an image that is similar to the original image but in a ratio specified by the scale factor.
- The ratio of the line segment formed from the center of dilation to a vertex in the new image and the corresponding vertex in the original image is equal to the scale factor.
MA19.GDA.27
Given two figures, determine whether they are similar by identifying a similarity transformation (sequence of rigid motions and dilations) that maps one figure to the other.
Teacher Vocabulary
- Corresponding pairs of angles
- Corresponding pairs of sides
- Proportionality
- Rigid Motion
- Similarity
- Similarity transformation
Knowledge
Students know:
- Properties of rigid motions and dilations.
- Definition of similarity in terms of similarity transformations.
- Techniques for producing images under dilation and rigid motions.
Skills
Students are able to:
- Apply rigid motion and dilation to a figure.
- Explain and justify whether or not one figure can be obtained from another through a combination of rigid motion and dilation.
Understanding
Students understand that:
- A figure that may be obtained from another through a dilation and a combination of translations, reflections, and rotations is similar to the original.
- When a figure is similar to another the measures of all corresponding angles are equal, and all of the corresponding sides are in the same proportion.
MA19.GDA.28
Verify criteria for showing triangles are similar using a similarity transformation (sequence of rigid motions and dilations) that maps one triangle to another.
MA19.GDA.28a
Verify that two triangles are similar if and only if corresponding pairs of sides are proportional and corresponding pairs of angles are congruent.
MA19.GDA.28b
Verify that two triangles are similar if (but not only if) two pairs of corresponding angles are congruent (AA), the corresponding sides are proportional (SSS), or two pairs of corresponding sides are proportional and the pair of included angles is congruent (SAS).
Teacher Vocabulary
- Corresponding pairs of angles
- Corresponding pairs of sides
- Proportionality
- Rigid Motion
- Similarity
- Similarity criteria for triangles
- Similarity transformation
Knowledge
Students know:
- The sum of the measures of the angles of a triangle is 180 degrees.
- Properties of rigid motions and dilations.
- Definition of similarity in terms of similarity transformations.
- Techniques for producing images under dilation and rigid motions.
Skills
Students are able to:
- Apply rigid motion and dilation to a figure.
- Explain and justify whether or not one figure can be obtained from another through a combination of rigid motion and dilation.
Understanding
Students understand that:
- A figure that may be obtained from another through a dilation and a combination of translations, reflections, and rotations is similar to the original.
- When a figure is similar to another the measures of all corresponding angles are equal, and all of the corresponding sides are in the same proportion.
MA19.GDA.29
Find patterns and relationships in figures including lines, triangles, quadrilaterals, and circles, using technology and other tools.
MA19.GDA.29a
Construct figures, using technology and other tools, in order to make and test conjectures about their properties.
MA19.GDA.29b
Identify different sets of properties necessary to define and construct figures.
Teacher Vocabulary
- Compass
- Congruent
- Conjectures
- Construct
- Straightedge
Knowledge
Students know:
- Use technology and other tools to discover patterns and relationships in figures.
- Use patterns. relationships and properties to construct figures.
Skills
Students are able to:
- Use properties to create methods for constructing different objects and prove that the constructions are accurate.
Understanding
Students understand that:
- Many of the constructions build on the relationships among the objects and are justified by the properties used during the construction.
- Technology can be used as a means to explain the properties and definitions by developing procedures to carry out the construction.
MA19.GDA.30
Develop and use precise definitions of figures such as angle, circle, perpendicular lines, parallel lines, and line segment, based on the undefined notions of point, line, distance along a line, and distance around a circular arc.
Teacher Vocabulary
- Angle
- Arc length
- Collinear
- Coplanar
- Distance
- Endpoint
- Line
- Parallel line
- Perpendicular line
- Plane
- Point
- Ray
- Segment
- Skew
- Vertex
Knowledge
Students know:
- Undefined notions of point, line, distance along a line, and distance around a circular arc.
- Properties of a mathematical definition, i.e., the smallest amount of information and properties that are enough to determine the concept. (Note: May not include all information related to the concept.)
Skills
Students are able to:
- Use known and developed definitions and logical connections to develop new definitions.
Understanding
Students understand that:
- Geometric definitions are developed from a few undefined notions by a logical sequence of connections that lead to a precise definition.
- A precise definition should allow for the inclusion of all examples of the concept, and require the exclusion of all non-examples.
MA19.GDA.31
Justify whether conjectures are true or false in order to prove theorems and then apply those theorems in solving problems, communicating proofs in a variety of ways, including flow chart, two-column, and paragraph formats.
MA19.GDA.31a
Investigate, prove, and apply theorems about lines and angles, including but not limited to: vertical angles are congruent; when a transversal crosses parallel lines, alternate interior angles are congruent and corresponding angles are congruent; the points on the perpendicular bisector of a line segment are those equidistant from the segment's endpoints.
MA19.GDA.31b
Investigate, prove, and apply theorems about triangles, including but not limited to: the sum of the measures of the interior angles of a triangle is $180^{\circ}$; the base angles of isosceles triangles are congruent; the segment joining the midpoints of two sides of a triangle is parallel to the third side and half the length; a line parallel to one side of a triangle divides the other two proportionally, and conversely; the Pythagorean Theorem using triangle similarity.
MA19.GDA.31c
Investigate, prove, and apply theorems about parallelograms and other quadrilaterals, including but not limited to both necessary and sufficient conditions for parallelograms and other quadrilaterals, as well as relationships among kinds of quadrilaterals.
Teacher Vocabulary
- Adjacent angles
- Alternate interior angles
- Base angles
- Bisect
- Centroid
- Complementary angles
- Consecutive interior angle
- Corresponding angles
- Diagonals
- Equidistant
- Equilateral triangles
- Exterior angles
- Interior angles of a triangle
- Isosceles triangles
- Linear pair
- Median
- Parallelograms
- Perpendicular bisector
- Prove
- Remote interior angles
- Same side interior angle
- Supplementary angles
- Theorem Proof
- Transversal
- Vertical angles
Knowledge
Students know:
- Requirements for a mathematical proof.
- Techniques for presenting a proof of geometric theorems.
Skills
Students are able to:
- Communicate logical reasoning in a systematic way to present a mathematical proof of geometric theorems.
- Generate a conjecture about geometric relationships that call for proof.
Understanding
Students understand that:
- Proof is necessary to establish that a conjecture about a relationship in mathematics is always true, and may also provide insight into the mathematics being addressed.
MA19.GDA.32
Use coordinates to prove simple geometric theorems algebraically.
Teacher Vocabulary
- Simple geometric figures
- Simple geometric theorems
Knowledge
Students know:
- Relationships (e.g., distance, slope of line) between sets of points.
- Properties of geometric shapes.
- Coordinate graphing rules and techniques.
- Techniques for presenting a proof of geometric theorems.
Skills
Students are able to:
- Accurately determine what information is needed to prove or disprove a statement or theorem.
- Accurately find the needed information and explain and justify conclusions.
- Communicate logical reasoning in a systematic way to present a mathematical proof of geometric theorems.
Understanding
Students understand that:
- Modeling geometric figures or relationships on a coordinate graph assists in determining the truth of a statement or theorem.
- Geometric theorems may be proven or disproven by examining the properties of the geometric shapes in the theorem through the use of appropriate algebraic techniques.
MA19.GDA.33
Prove the slope criteria for parallel and perpendicular lines and use them to solve geometric problems.
Teacher Vocabulary
- Parallel lines
- Perpendicular lines
- Slope
- Slope triangle
Knowledge
Students know:
- Techniques to find the slope of a line.
- Key features needed to solve geometric problems.
- Techniques for presenting a proof of geometric theorems.
Skills
Students are able to:
- Explain and justify conclusions reached regarding the slopes of parallel and perpendicular lines.
- Apply slope criteria for parallel and perpendicular lines to accurately find the solutions to geometric problems and justify the solutions.
- Communicate logical reasoning in a systematic way to present a mathematical proof of geometric theorems.
Understanding
Students understand that:
- Relationships exist between the slope of a line and any line parallel or perpendicular to that line.
- Slope criteria for parallel and perpendicular lines may be useful in solving geometric problems.
MA19.GDA.34
Use congruence and similarity criteria for triangles to solve problems in real-world contexts.
Teacher Vocabulary
- Congruence criteria for triangles
- Similarity criteria for triangles
Knowledge
Students know:
- Criteria for congruent (SAS, ASA, AAS, SSS) and similar (AA) triangles and transformation criteria.
- Techniques to apply criteria of congruent and similar triangles for solving a contextual problem.
- Techniques for applying rigid motions and dilations to solve congruence and similarity problems in real-world contexts.
Skills
Students are able to:
- Accurately solve a contextual problem by applying the criteria of congruent and similar triangles.
- Provide justification for the solution process.
- Analyze the solutions of others and explain why their solutions are valid or invalid.
- Justify relationships in geometric figures through the use of congruent and similar triangles.
Understanding
Students understand that:
- Congruence and similarity criteria for triangles may be used to find solutions to contextual problems.
- Relationships in geometric figures may be proven through the use of congruent and similar triangles.
MA19.GDA.35
Discover and apply relationships in similar right triangles.
MA19.GDA.35a
Derive and apply the constant ratios of the sides in special right triangles ( and ).
MA19.GDA.35b
Use similarity to explore and define basic trigonometric ratios, including sine ratio, cosine ratio, and tangent ratio.
MA19.GDA.35c
Explain and use the relationship between the sine and cosine of complementary angles.
MA19.GDA.35d
Demonstrate the converse of the Pythagorean Theorem.
MA19.GDA.35e
Use trigonometric ratios and the Pythagorean Theorem to solve right triangles in applied problems, including finding areas of regular polygons.
Teacher Vocabulary
- Complementary angles
- Converse
- Cosecant
- Cosine
- Cotangent
- Secant
- Side ratios
- Sine
- Tangent
- Trigonometric ratios
Knowledge
Students know:
- Techniques to construct similar triangles.
- Properties of similar triangles.
- Methods for finding sine and cosine ratios in a right triangle (e.g., use of triangle properties such as similarity, the Pythagorean theorem, isosceles and equilateral characteristics for 45-45-90 and 30-60-90 triangles, and technology for others).
- Methods of using the trigonometric ratios to solve for sides or angles in a right triangle.
- The Pythagorean theorem and its use in solving for unknown parts of a right triangle.
Skills
Students are able to:
- Accurately find the side ratios of triangles.
- Explain and justify relationships between the side ratios of a right triangle and the angles of a right triangle.
Understanding
Students understand that:
- The ratios of the sides of right triangles are dependent on the size of the angles of the triangle.
- The sine of an angle is equal to the cosine of the complement of the angle.
- Switching between using a given angle or its complement and between sine or cosine ratios may be used when solving contextual problems.
MA19.GDA.36
Use geometric shapes, their measures, and their properties to model objects and use those models to solve problems.
Teacher Vocabulary
- Model
Knowledge
Students know:
- Techniques to find measures of geometric shapes.
- Properties of geometric shapes.
Skills
Students are able to:
- Model a real-world object through the use of a geometric shape.
- Justify the model by connecting its measures and properties to the object.
Understanding
Students understand that:
- Geometric shapes may be used to model real-world objects.
- Attributes of geometric figures help us identify the figures and find their measures, therefore, matching these figures to real-world objects allows the application of geometric techniques to real-world problems.
MA19.GDA.37
Investigate and apply relationships among inscribed angles, radii, and chords, including but not limited to: the relationship between central, inscribed, and circumscribed angles; inscribed angles on a diameter are right angles; the radius of a circle is perpendicular to the tangent where the radius intersects the circle.
Teacher Vocabulary
- Central angles
- Chord
- Circumscribed
- Circumscribed angles
- Inscribed angles
- Perpendicular arc
- Tangent
Knowledge
Students know:
- Definitions and characteristics of central, inscribed, and circumscribed angles in a circle.
- Techniques to find measures of angles including using technology (dynamic geometry software).
Skills
Students are able to:
- Explain and justify possible relationships among central, inscribed, and circumscribed angles sharing intersection points on the circle.
- Accurately find measures of angles (including using technology, such as dynamic geometry software) formed from inscribed angles, radii, chords, central angles, circumscribed angles, and tangents.
Understanding
Students understand that:
- Relationships that exist among inscribed angles, radii, and chords may be used to find the measures of other angles when appropriate conditions are given.
- Identifying and justifying relationships exist in geometric figures.
MA19.GDA.38
Use the mathematical modeling cycle involving geometric methods to solve design problems.
Teacher Vocabulary
- Density
- Design problems
- Geometric methods
- Typographic grid system
Knowledge
Students know:
- Properties of geometric shapes.
- Characteristics of a mathematical model.
- How to apply the mathematical modeling cycle to solve design problems.
Skills
Students are able to:
- Accurately model and solve a design problem.
- Justify how their model is an accurate representation of the given situation.
Understanding
Students understand that:
- Design problems may be modeled with geometric methods.
- Geometric models may have physical constraints.
- Models represent the mathematical core of a situation without extraneous information, for the benefit of a problem-solving situation.