The complement of an angle is 25°. What is the measure of the angle?

Complement of an alngle means what you need to add to it to make 90 degrees

comlement of angle x is y such that x+y=90

so if complement of angle x is 25, that means the angle x is found by

x+25=90

minus 25 both sides

x=65 degrees

the angle measures 65 degree

Complimentary angles add up to 90 degrees so if the compliment to an angle of 25 degrees you would do

90 - 25 = 65 degrees