Question 388146
 9x+2y=36     subtract both equations to eliminate x
 9x+8y=36
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   -6y=0
     y=0/-6=0

substitue y=0 in equation 1 (you can sustitute in either equation will yield same answer, i'm using 1)

9x+2(0)=36
x=36/9
x=4

thus, x=4 and y=0 is the answer


check:
sub. x and y in both equations to see if LHS=RHS
9x+2y=9(4)+2(0)=36
9x+8y=9(4)+8(0)=36

thus, LHS=RHS, 36=36 correct answer