SOLUTION: if -2x+7y=-8 and x-6y=10 then what does x-y equal?

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Question 144185: if -2x+7y=-8 and x-6y=10 then what does x-y equal?
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
-2x+7y=-8 and x-6y=10 then what does x-y equal?
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EQUATIONS:
-2x + 7y = -8
x - 6y = 10
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x = 6y + 10
Substitute to get:
-2(6y+10) + 7y = -8
-12y - 20 + 7y = -8
-5y = 12
y = -12/5
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Substitute into x = 6y +10 to solve for "x":
x = 6(-12/5) +10
x = (-72/5) + (50/5)
x = -22/5
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So x-y = -22/5 - (-12/5) = -10/5 = -2
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Cheers,
Stan H.