SOLUTION: angle A and angle B are supplementary. angle A is 20 more than 3 times angle B. how many degrees is angle B. please help

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Question 615874: angle A and angle B are supplementary. angle A is 20 more than 3 times angle B. how many degrees is angle B. please help
Answer by dragonwalker(73) About Me  (Show Source):
You can put this solution on YOUR website!
So supplementary angles means they add up to 180 degrees
as angle B is smaller then we should give it value x.
So we have to find a formula that fits the size of Angle A.
it is three time angle B + 20
so: 3 times x +20
3x+20
So angle A is 3x+20
angle B is x
Adding these together equals 180 so:
3x+20 + x = 180
solve for x:
4x + 20 = 180
4x = 180-20
4x = 160
x = 160/4
x = 40
So angle B is 40 degrees.
To check. this would mean that angle A is 3 times 40 plus 20 = 120 + 20
= 140
Add 140 + 40 = 180 !!!