SOLUTION: Please help me solve using the substitution method 7x+3y=-25 -7x+y=29

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Question 240544: Please help me solve using the substitution method
7x+3y=-25
-7x+y=29

Answer by unlockmath(1688) About Me  (Show Source):
You can put this solution on YOUR website!
Hello,
Let's take the second equation and get y alone. To do that we add 7x to both sides. That will give us:
y=7x+29 Now we can put this into the first equation:
7x+3(7x+29)=-25 Distribute and combine like terms we get:
28x + 87=-25 Now subtract 87 from both sides gives us:
28x = -112 Divide both sides by 28 gives us:
x = -4 To find y just plug -4 into either equation and we get:
y=1 To see if these are right plug both values into both equations and it should come out the same.
RJ Toftness
www.math-unlock.com