### Home > CC3MN > Chapter 9 > Lesson 9.1.3 > Problem9-46

9-46.

For each diagram below, solve for $x$. Explain what method you used for each problem.

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

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

$x=20°$

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

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

$x + 30 + 90 = 180$

$x + 120 = 180$

$x=60°$