If two angles are complementary, and one angle measures 30°, what is the measure of the other angle?

When two angles are considered complementary, it means that the sum of their measures is always equal to 90 degrees. In this case, one angle is given as 30 degrees. To find the measure of the other angle, you subtract the measure of the known angle from 90 degrees.

So, the calculation would be:

90° - 30° = 60°

This result indicates that the other angle measures 60 degrees. Therefore, the correct answer is 60°.

Understanding complementary angles is essential in various mathematical contexts, including geometry and trigonometry, as it lays the groundwork for more complex relationships between angles.