Chapter 3 - Equations and Problem Solving - 3.3 - More on Solving Equations and Problem Solving - Problem Set 3.3 - Page 115: 55

The two angles are 50 and 130.

Let X represent the smaller angle. Three times the smaller angle means 3X 20 less than three times the smaller angle means 3X - 20 Since the two angles are supplementary, their sum is 180. Thus, we obtain: X + 3X - 20 = 180 4X - 20 = 180 Add 20 to both sides 4X = 200 Divide both sides by 4 X = 50 Since X = 50, 3X - 20 = 130 The two angles are 50 and 130.