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Math
English Language Arts
Science
Blended
Math
English Language Arts
Science
Blended Learning
Math
Kindergarten
Counting & Cardinality
Operations & Algebraic Thinking
Number & Operations in Base Ten
Measurement and Data
Geometry
First Grade
Operations & Algebraic Thinking
Number & Operations in Base Ten
Measurement and Data
Geometry
Second Grade
Operations & Algebraic Thinking
Number & Operations in Base Ten
Measurement and Data
Geometry
Third Grade
Operations & Algebraic Thinking
Number & Operations in Base Ten
Numbers & Operations-Fractions
Measurement and Data
Geometry
Fourth Grade
Operations & Algebraic Thinking
Number & Operations in Base Ten
Number & Operations—Fractions
Measurement and Data
Geometry
Fifth Grade
Operations & Algebraic Thinking
Number & Operations in Base Ten
Number & Operations—Fractions
Measurement & Data
Geometry
Sixth Grade
Ratios & Proportional Relationships
The Number System
Expressions & Equations
Geometry
Statistics & Probability
Seventh Grade
Ratios & Proportional Relationships
The Number System
Expressions & Equations
Geometry
Statistics & Probability
Eighth Grade
The Number System
Expressions & Equations
Functions
Geometry
Statistics & Probability
HS Number & Quantity
The Real Number System
Quantities
The Complex Number System
Vector & Matrix Quantities
HS Algebra
Seeing Structure in Expressions
Arithmetic with Polynomials & Rational Expressions
Creating Equations*
Reasoning with Equations & Inequalities
HS Functions
Interpreting Functions
Building Functions
Linear, Quadratic, & Exponential Models*
Trigonometric Functions
HS Geometry
Congruence
Similarity, Right Triangles, & Trigonometry
Circles
Expressing Geometric Properties with Equations
Geometric Measurement & Dimension
Modeling with Geometry
HS Statistics & Probability
Interpreting Categorical & Quantitative Data
Making Inferences & Justifying Conclusions
Conditional Probability & the Rules of Probability
Using Probability to Make Decisions
Back
HSG-CO.C.11
HS Geometry
Congruence
Congruence
Similarity, Right Triangles, & Trigonometry
Circles
Expressing Geometric Properties with Equations
Geometric Measurement & Dimension
Modeling with Geometry
HSG-CO.C.11
HSG-CO.C.9
Prove theorems about lines and angles. Theorems include: vertical angles are congruent; when a transversal crosses parallel lines, alternate interior angles are congruent and corresponding angles are congruent; points on a perpendicular bisector of a line segment are exactly those equidistant from the segment's endpoints.
HSG-CO.C.10
Prove theorems about triangles. Theorems include: measures of interior angles of a triangle sum to 180 degrees; base angles of isosceles triangles are congruent; the segment joining midpoints of two sides of a triangle is parallel to the third side and half the length; the medians of a triangle meet at a point.
HSG-CO.C.11
Prove theorems about parallelograms. Theorems include: opposite sides are congruent, opposite angles are congruent, the diagonals of a parallelogram bisect each other, and conversely, rectangles are parallelograms with congruent diagonals.
HSG-CO.C.11
Prove theorems about parallelograms. Theorems include: opposite sides are congruent, opposite angles are congruent, the diagonals of a parallelogram bisect each other, and conversely, rectangles are parallelograms with congruent diagonals.
42 Lessons
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HSG-CO.C.9
Prove theorems about lines and angles. Theorems include: vertical angles are congruent; when a transversal crosses parallel lines, alternate interior angles are congruent and corresponding angles are congruent; points on a perpendicular bisector of a line segment are exactly those equidistant from the segment's endpoints.
HSG-CO.C.10
Prove theorems about triangles. Theorems include: measures of interior angles of a triangle sum to 180 degrees; base angles of isosceles triangles are congruent; the segment joining midpoints of two sides of a triangle is parallel to the third side and half the length; the medians of a triangle meet at a point.
HSG-CO.C.11
Prove theorems about parallelograms. Theorems include: opposite sides are congruent, opposite angles are congruent, the diagonals of a parallelogram bisect each other, and conversely, rectangles are parallelograms with congruent diagonals.