### Home > ACC7 > Chapter cc39 > Lesson cc39.2.3 > Problem 9-96

9-96.

For each diagram below, solve for

*x*. Explain what method you used for each problem. Homework Help ✎a.

b.

c.

d.

The two angles are complementary, meaning they have a sum of 90°.

The two angles are supplementary (have a sum of 180°).

*x* = 20°

According to the Angle Sum Theorem, the sum of the interior angles of a triangle is 180°.

How did you solve part (c)? Use the same method.

*x* + 30 + 90 = 180

*x* + 120 = 180

*x* = 60°