All triangles have some things in common. Using these properties of triangles, learners find missing angle measures. Scholars use the Angle Sum Property and properties of special triangles throughout the instructional activity.

Review for the test with a comprehensive list of terms and concepts for the unit on congruence and similarity. It divides divides the sections in the order of the lessons presented during the unit. 

Stuck trying to remember the formal language of a geometric proof? Never fear, this handout has them all ready to go. The reasons are sectioned by topic so this handy guide is ready when you are to tackle those two column proofs. 

Here is a partial list of theorems, postulates, and properties.

[Free Registration/Login may be required to access all resource tools.] Provides an overview of triangle congruence, including key terms, properties of congruent triangles, triangle postulates and theorems, and special triangles.

This site defines eleven theorems relating to parallel lines and similar and congruent triangles. Links to the theorems and relevant term descriptions are provided.

Explains the basic concept of similar triangles with step-by-step instructions and methods for solving specific problems on your own relating to this topic.

Explains the basic concept of congruent triangles with step-by-step instructions and methods for solving specific problems on your own relating to this topic.

[Free Registration/Login may be required to access all resource tools.] This study guide looks at the definitions and units for perimeter, area, and circumference, and at the perimeter and area of different shapes, including regular...