SOLUTION: I need to know how to solve these equations using substitution thanks:) -x+y=7 and -1/2x-y=2

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Question 601777: I need to know how to solve these equations using substitution thanks:)
-x+y=7 and -1/2x-y=2
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
solve these equations using substitution thanks:)
-x+y=7
-1/2x-y=2
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Solve either of the equations for x or for "y":
y = x+7
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Substitute into the other equation:
(-1/2)x -(x+7) = 2
(-1/2)x - x - 7 = 2
---
(-3/2)x = 9
x = (-2/3)9
x = -6
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solve for "y":
y = x + 7
y = -6+7
y = 1
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Cheers,
Stan H.