SOLUTION: The measure of ∠A is 8° more than three times the measure of ∠B. If A and B are supplementary angles, find the measure of ∠A.

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Question 357935: The measure of ∠A is 8° more than three times the measure of ∠B. If A and B are supplementary angles, find the measure of ∠A.
Found 2 solutions by Fombitz, MathTherapy:
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
By definition,
A%2BB=180
.
.
.
A=8%2BB
Substitute,
8%2BB%2BB=180
2B=172
highlight%28B=86%29degrees
Then
A=8%2B86
highlight%28A=94%29degrees

Answer by MathTherapy(10556) About Me  (Show Source):
You can put this solution on YOUR website!
The measure of ∠A is 8° more than three times the measure of ∠B. If A and B are supplementary angles, find the measure of ∠A.

Since angle A is 8° more than three times the measure of angle B, then we can say that: A = 3B + 8, or A - 3B = 8

Since angles A and B are supplementary angles, then we can say that: A + B = 180

We therefore have:

A + B = 180__________eq (i)
A - 3B = 8__________eq (ii)
3A + 3B = 540__________eq (iii) ------ Multiplying eq (i) by 3

4A = 548 ------ Adding eq (ii) & (iii)

Angle A = 548%2F4 = highlight_green%28137%5Eo%29