Chapter 4 - Congruent Triangles - 4-5 Isosceles and Equilateral Triangles - Practice and Problem-Solving Exercises - Page 256: 32

𝑚 = 60 degrees 𝑛 = 30 degrees

Equilateral triangle - all angles are 60 degrees by definition - given Right triangle = 90 degrees by definition - given 90 = 𝑛 + 60 𝑛 = 30 degrees 𝑚 + 𝑛 + 90 = 180 𝑚 + 30 + 90 = 180 𝑚 + 120 = 180 𝑚 = 60 degrees