Two angles are complementary, and one of them is 18° more than the other. What is the smaller angle?

Explanation

1. 01

   Complementary angles add up to 90°.

2. 02

   Let the smaller angle be $x$. Then $x + (x + 18^\circ) = 90^\circ$, so $2x = 72^\circ$ and $x = 36^\circ$.