SOLUTION: how do you do 2x+7y=-20 and y=3x+7

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Question 556076: how do you do 2x+7y=-20 and y=3x+7
Answer by rfer(16322) About Me  (Show Source):
You can put this solution on YOUR website!
2x+7(3x+7)=-20
2x+21x+49=-20
23x=-69
x=-3
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2*-3+7y=-20
-6+7y=-20
7y=-14
y=-14/7
y=-2
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y=3*-3+7
y=-9+7
y=-2