Question

Plz help me on this I really need help

Answer 1

Let
`x = m\angle B`. "The measure of angle A is three times the measure of angle B." So
`m\angle A = 3x`.

The angles are supplementary. What does that word mean? Their measures add up to 180 degrees.

`3x+x=180 \\ 4x = 180 \\ x = 45^\circ`

The measure of angle A is 3(45) = 135, and the measure of angle B is 45.