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 + y = 90`

`x = 3y`

`3y + y = 90`

`4y = 90`

`y = 15`

`x = 3(15) = 45`

Answer 2

45 °

Explanation:

Knowing that:

Supplementary Angle = 180 °

Angle x is 3 time the measure of angle y.

Solve:

Equation below:

x + y = 180

x = 3y

Substitute

3y + y =180

4y = 180

Divide both sides by 4

4y/4 = 180/4

y = 45

Value of x:

x = 3 × 45

x = 135

Therefore the measure of angle x is 135.

x = 45

y = 135

~Lenvy~