Question

Angle A and angle B are supplementary angles. If

angle B is 30° more than four times angle A, find
angle A and angle B.​

Answer 1

Angle A is 30

Angle B is 150

Explanation:

So we have the supplementary angles A and B. In other words:

`A+B=180`

We are also told that Angle B is 30 more than four times Angle A. In an equation, this is:

`B=30+4A`

We now have a system of equations. Solve by substitution of B into the first equation:

`A+B=180`

`A+(30+4A)=180`

Combine like terms:

`5A+30=180`

Subtract 30:

`5A=150`

Divide by 5:

`A=30`

So, Angle A is 30 degrees.

And since the angles are supplementary, this means that Angle B is 180 minus 30 or 150 degrees.