SOLUTION: solve the following system of equations 6x+7y=4 6x+9y=12

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Question 880895: solve the following system of equations
6x+7y=4
6x+9y=12
Answer by LinnW(1048) About Me  (Show Source):
You can put this solution on YOUR website!
6x+7y=4
6x+9y=12
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-1(6x+7y=4) = -6x-7y=-4
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-6x-7y=-4
6x+9y=12
2y = 8
y = 4
Substitute 4 for y in 6x+7y=4
6x+7(4)=4
6x + 28 = 4
add -28 to each side
6x = -24
divide each side by 6
x = -4