CPM Homework Banner

Home > CCG > Chapter 7 > Lesson 7.2.5 > Problem 7-98


, , and are exterior angles of the triangle at right. Find , , and . Then find .  

How do the angles within a triangle relate to each other? How do the exterior angles relate to those within the triangle?

Three lines intersect each other to form a triangle. Each line extends past a vertex such that 48 degrees is an angle within the triangle and angle, a, is the external angle. 72 degrees is internal and angle, b, is external to it. Angle, c, is the external angle of the third internal angle.