SOLUTION: 3x+4y=-12 -x+y=5

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Question 312157: 3x+4y=-12
-x+y=5
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
1.3x%2B4y=-12
2.-x%2By=5
Multiply eq. 2 by 3 and add them together,
3x%2B4y-3x%2B3y=-12%2B15
7y=-3
y=highlight_green%28-3%2F7%29
Then from eq. 2,
-x%2By=5
-x%2B3%2F7=5
-x=35%2F7-3%2F7
highlight_green%28x=32%2F7%29