1. The problem is to find which angles are complementary. 2. Complementary angles are two angles whose measures add up to 90 degrees. 3. The formula for complementary angles is: $$\text{Angle}_1 + \text{Angle}_2 = 90^\circ$$ 4. To check if two angles are complementary, add their measures and see if the sum equals 90. 5. For example, if one angle is $30^\circ$, the complementary angle is: $$90^\circ - 30^\circ = 60^\circ$$ 6. Therefore, $30^\circ$ and $60^\circ$ are complementary angles. 7. In summary, any two angles that add up to $90^\circ$ are complementary.