SOLUTION: Please solve this of substitution 5x-9y=29 12x+y=47

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Question 807678: Please solve this of substitution
5x-9y=29
12x+y=47

Answer by KMST(5328) About Me  (Show Source):
You can put this solution on YOUR website!
To solve a system of linear equations like system%285x-9y=29%2C12x%2By=47%29 by substitution,
we solve one equation for one variable,
and substitute the expression found for that variable into the other equation.

In the case of system%285x-9y=29%2C12x%2By=47%29 , the easiest start is
to solve for y in 12x%2By=47 .
12x%2By=47
y=47-12x
Substituting 47-12x for y in 5x-9y=29 we get
5x-9%2847-12x%29=29
5x-423%2B108x=29
5x%2B108x=29%2B423
113x=452
x=452%2F113
highlight%28x=4%29
Now, we plug that value into y=47-12x to find y :
y=47-12%2A4
y=47-48
highlight%28y=-1%29