SOLUTION: Solve the system by addition -3x+4y=-6 x-2y=12

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Question 106658: Solve the system by addition
-3x+4y=-6
x-2y=12

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
Solve the system by addition
1st: -3x+4y=-6
2nd: x-2y=12
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Multiply 2nd by 3 to get:
3rd: 3x-6y=36
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Add 1st and 3rd to get:
-2y= 30
y=-15
Substitute into x-2y=12 to solve for x:
x-2*-15 = 12
x+30=12
x = -18
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Cheers,
Stan H.