SPECIALTIES WITH TRIANGLES AND INDIRECT PROOFS

In this unit you will learn about special characteristics in a triangle. You will examine medians which are line segments from vertices to the midpoints of their opposite sides. You will also examine the altitudes of triangles which are perpendicular line segments from the vertices to their opposite sides. You will learn new postulates including the “Hy-Leg Postulate” for right triangle congruency. You will reexamine perpendicular and angle bisectors, and then explore the equidi stance theorems about bisectors. The unit will close with creating “indirect” proofs which is a new strategy for proving theorems by stating a contradiction.

Review: Triangle Basics (02:04)

Isosceles and Right Triangle Theorems (05:40)

Review: World of Triangles (01:11)

Below are additional educational resources and activities for this unit.

Medians

Multi-Step Special Right Triangles