Answer:
x = 18°
Explanation:
Adjacent angles:
Two angles are adjacent if they have a common arm and a common vertex.
Complementary angles:
Two angles are complementary, if they add up to 90°.
These angles in the figure are adjacent angles as they have a common arm. The adjacent angles are complementary.
3x + 2x = 90
Combine like terms,
5x = 90
Divide both sides by 5,
x = 90 ÷ 5
