Question

Angles x and y are supplementary. angle x is 3 times the measure of angle y. what is the measure of angle x? 45� 60� 120� 135�

Answer 1

x = 135°

Explanation:

supplementary angles sum to 180° , that is

x + y = 180° ← substitute x = 3y into the equation

3y + y = 180°

4y = 180° ( divide both sides by 4 )

y = 45°

now

x + y = 180°

x + 45° = 180° ( subtract 45° from both sides )

x = 135°