Question

Recall that two angles are complementary if the sum of their measures is 90°. Find the measures of two complementary angles if one angle is four times the other angle.

Answer 1

18° and 72°

Explanation:

The angle measures are unknown, so they will be represented with the variable, x. Since, one angle is 4 times the other, this will be represented with 4x.

To find complementary angles, they are added together and equal 90. So let's create an equation.

x + 4x = 90

Now solve for x.

5x = 90

5x/5 = 90/5

x = 18

One angle is 18°.

Now find the second angle.

4x

plugin 18 for x and multiply

4(18) = 72