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

3x + x = 180

4x = 180

x = 45

Angle y = 45

Multiply 45 * 3 = 135

<x = 135

Answer 2

we know that

Supplementary angles are those angles whose sum is equal to
`180` degrees

In this problem

`x+y=180` --------> equation
`1`

`x=3y` --------> equation
`2`

Substitute the equation
`2` in equation
`1`

`[3y]+y=180`

`4y=180`

`y=45`°

Find the value of x

`x=3*45`

`x=135`°

therefore

the answer is

The measure of angle x is
`135`°