Final answer:
The measure of the complementary angle of 69° is 21°.
Step-by-step explanation:
The complementary angle of a given angle is the angle that, when added to the given angle, results in a sum of 90 degrees. To find the measure of the complementary angle of 69 degrees, we subtract 69 from 90.
90 degrees - 69 degrees = 21 degrees
Therefore, the measure of the complementary angle of 69 degrees is 21 degrees.