SOLUTION: Can you help me solve this equation with substitution -5x - 7y = -15 x + 2y = 6

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Question 719830: Can you help me solve this equation with substitution
-5x - 7y = -15
x + 2y = 6
Found 2 solutions by MathLover1, stanbon:
Answer by MathLover1(20849) About Me  (Show Source):
You can put this solution on YOUR website!

-5x+-+7y+=+-15..eq.1
x+%2B+2y+=+6...eq.2
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start with x+%2B+2y+=+6...eq.2 and solve for x

x=+6-2y...eq.2a....substitute in eq.1

-5%286-2y%29+-+7y+=+-15..eq.1...solve for y

-30%2B10y+-7y+=+-15
3y+=+-15%2B30
3y+=+15
y+=+15%2F3
highlight%28y+=+5%29...go back to eq.2a, substitute 5 for y and solve for x
x=+6-2%2A5...eq.2a
x=+6-10
highlight%28x=+-4%29

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
solve this equation with substitution
-5x - 7y = -15
x + 2y = 6
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Modify then substitute:
x = 6-2y
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-5(6-2y)-7y = -15
-30 + 10y - 7y = -15
3y = 15
y = 5
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Solve for "x":
x = 6-2y
x = 6-2*5
x = -4
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Cheers,
Stan H.
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