The measure of an angle is 4 times the measure of its complement. What is the measure of the angle's supplement?

5 answers

5x = 90

x = ?
18
18 is the complementary angle. Now find the supplementary angle.

18 + X = 180

http://www.mathsisfun.com/geometry/supplementary-angles.html
let the angle be x
then its complement is 90-x

x = 4(90-x)
x = 360 - 4x
5x = 360
x = 72

so the angle is 72°
and its supplement is 180-72 = 108°

check:
our angle = 72
its complement = 18
is the angle 4 times its complement ?
is 72 = 4(18) ? yes
The measure of an angle is 4 times the measure of its complement. What is the measure of the angle's supplement?