Let x be the measure of the angle and y be the measure of its complement.
Given that the complement angle is 15 degrees less than x, that is, y = x - 15.
Use the relation that sum of an angle and its complement equals 90 degrees. So,

Substitute x-15 for y into the equation.

The measure of the angle is 52.5 degrees and of its complement is 37.5 degrees.