Unit 4: Triangle Congruence 4.8 Isosceles and Equilateral Triangles (Part 2)
Warm Up 11/28 (HW #21 [4.8] Page 277 #s 13 – 20) 1. Find each angle measure. True or False. Explain your reasoning. 2. Every equilateral triangle is isosceles. 3. Every isosceles triangle is equilateral.
Prove theorems about equilateral triangles. Apply properties of equilateral triangles. Objectives *Standard 12.0 Students find and use measures of sides and of interior and exterior angles of triangles and polygons to classify figures and solve problems.
The following corollary and its converse show the connection between equilateral triangles and equiangular triangles. (see pages 274 & 275)
Example 3A: Using Properties of Equilateral Triangles (see page 275) Find the value of x and m M.
Example 3B: Using Properties of Equilateral Triangles (see page 275) Find the value of y and NP.
Check It Out! Example 3 (see page 275) Find the value of t and JL.
1. Find the value of x and m A. A B C
2. Find the value of y and DE. D E F