## CCSS.MATH.CONTENT.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.

There are 29 resources.
Title Description Thumbnail Image Curriculum Topics

## Definition--Geometry Basics--Perpendicular Bisector

Definition--Geometry Basics--Perpendicular Bisector

This collection of clip art images includes image sequences for key topics in geometry. This includes points, lines, planes, angles, triangles, quadrilaterals, and polygons. Each sequence of images provides an overview of the topic.

Definition of a Line

## Definition--Theorems and Postulates--AAA Theorem

Definition--Theorems and Postulates--AAA Theorem

This is part of a collection of definitions of geometric theorems and postulates.

Definition of a Triangle

## Definition--Theorems and Postulates--AAS Theorem

Definition--Theorems and Postulates--AAS Theorem

This is part of a collection of definitions of geometric theorems and postulates.

Definition of a Triangle

## Definition--Theorems and Postulates--Alternate Interior Angles Theorem

Definition--Theorems and Postulates--Alternate Interior Angles Theorem

This is part of a collection of definitions of geometric theorems and postulates.

Definition of an Angle

## Definition--Theorems and Postulates--ASA Theorem

Definition--Theorems and Postulates--ASA Theorem

This is part of a collection of definitions of geometric theorems and postulates.

Definition of an Angle

## Definition--Theorems and Postulates--Converse of Same-Side Interior Angles Postulate

Definition--Theorems and Postulates--Converse of Same-Side Interior Angles Postulate

This is part of a collection of definitions of geometric theorems and postulates.

Definition of an Angle

## Definition--Theorems and Postulates--Converse of the Alternate Interior Angles Theorem

Definition--Theorems and Postulates--Converse of the Alternate Interior Angles Theorem

This is part of a collection of definitions of geometric theorems and postulates.

Definition of an Angle

## Definition--Theorems and Postulates--Converse of the Corresponding Angles Theorem

Definition--Theorems and Postulates--Converse of the Corresponding Angles Theorem

This is part of a collection of definitions of geometric theorems and postulates.

Definition of an Angle

## Definition--Theorems and Postulates--Corresponding Angles Theorem

Definition | Theorems and Postulates | Corresponding Angles Theorem

This is part of a collection of definitions of geometric theorems and postulates.

Definition of an Angle

## Definition--Theorems and Postulates--Perpendicular Bisector Theorem

Definition--Theorems and Postulates--Perpendicular Bisector Theorem

This is part of a collection of definitions of geometric theorems and postulates.

Definition of a Line

## Definition--Theorems and Postulates--Same-Side Interior Angles Postulate

Definition--Theorems and Postulates--Same-Side Interior Angles Postulate

This is part of a collection of definitions of geometric theorems and postulates.

Definition of a Triangle

## Definition--Theorems and Postulates--SAS Similarity Theorem

Definition--Theorems and Postulates--SAS Similarity Theorem

This is part of a collection of definitions of geometric theorems and postulates.

Definition of a Triangle

## Definition--Theorems and Postulates--SAS Theorem

Definition--Theorems and Postulates--SAS Theorem

This is part of a collection of definitions of geometric theorems and postulates.

Definition of a Triangle

## Definition--Theorems and Postulates--SSS Postulate

Definition--Theorems and Postulates--SSS Postulate

This is part of a collection of definitions of geometric theorems and postulates.

Definition of a Triangle

## Math Clip Art--Angle Illustrations--Supplementary Angles--Labeled

Math Clip Art--Angle Illustrations--Supplementary Angles--Labeled

This is part of a collection of clip art images showing different types of angles. Each type of angle measure includes a labeled and unlabeled version.

Angles, Applications of Angles and Planes

## Math Clip Art--Angle Illustrations--Supplementary Angles--Unlabeled

Math Clip Art--Angle Illustrations--Supplementary Angles--Unlabeled

This is part of a collection of clip art images showing different types of angles. Each type of angle measure includes a labeled and unlabeled version.

Angles, Applications of Angles and Planes

## Math Example--Geometric Proofs--Example 1

Math Example--Geometric Proofs--Example 1

This is part of a collection of math examples that focus on geometric proofs.

Parallel Lines, Definition of a Triangle

## Math Example--Geometric Proofs--Example 10

Math Example--Geometric Proofs--Example 10

This is part of a collection of math examples that focus on geometric proofs.

Parallel Lines, Definition of a Triangle

## Math Example--Geometric Proofs--Example 11

Math Example--Geometric Proofs--Example 11

This is part of a collection of math examples that focus on geometric proofs.

Parallel Lines, Definition of a Triangle

## Math Example--Geometric Proofs--Example 12

Math Example--Geometric Proofs--Example 12

This is part of a collection of math examples that focus on geometric proofs.

Parallel Lines, Definition of a Triangle

## Math Example--Geometric Proofs--Example 13

Math Example--Geometric Proofs--Example 13

This is part of a collection of math examples that focus on geometric proofs.

Parallel Lines, Definition of a Triangle

## Math Example--Geometric Proofs--Example 2

Math Example--Geometric Proofs--Example 2

This is part of a collection of math examples that focus on geometric proofs.

Parallel Lines, Definition of a Triangle

## Math Example--Geometric Proofs--Example 3

Math Example--Geometric Proofs--Example 3

This is part of a collection of math examples that focus on geometric proofs.

Parallel Lines, Definition of a Triangle

## Math Example--Geometric Proofs--Example 4

Math Example--Geometric Proofs--Example 4

This is part of a collection of math examples that focus on geometric proofs.

Parallel Lines, Definition of a Triangle

## Math Example--Geometric Proofs--Example 5

Math Example--Geometric Proofs--Example 5

This is part of a collection of math examples that focus on geometric proofs.

Parallel Lines, Definition of a Triangle