Question 232888
 9x+3y= -39
-9x+y = 71
y= 71+9x 
9x+3(71+9x)= -39 
9x+213+27x = -39 
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36x + 213 = -39
36x = -252
x = -7
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y = 71+9x = 71 - 63
y = 8
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Elimination would have been easier for this one, since the coefficients of x are the same.
 9x+3y= -39
-9x+y = 71
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0x + 4y = 32
y = 8
-----  etc