SOLUTION: solve by the elimination method 5x-9y=-71 9x+5y=63

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Question 757428: solve by the elimination method
5x-9y=-71
9x+5y=63

Answer by LearnWithMajor(33) About Me  (Show Source):
You can put this solution on YOUR website!
To solve by elimination we first need to have the coefficients in front of one variable to be the same. For this problem I am going to eliminate y.
5x-9y=-71
9x+5y=63
5(5x-9y=-71)
9(9x+5y=63)
25x-45y=-355
81x%2B45y=567
Now that the coefficients in front of the y's are the same I am going to add the two equations together because the signs in front of the coefficients are different (if they were the same we would need to subtract)
25x-45y=-355
+81x+45y=567
25x%2B81x+=+-355%2B567
106x+=+212
x+=+2
Plug x back into one of the original equations to solve for y.
9%282%29%2B5y+=+63
18+%2B+5y+=+63
5y+=+45
y+=+9