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 lesson.

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. 

[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.