10x+2y=18
10x-7y=-18
Multiply the second one by -1
-10x+7y=18
Then add the two equations
10x+2y=18
+-10x+7y=18
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9y=36
y=4
Plug that back into one of the equations above and solve for x
10x+2y=18
10x+2(4)=18
10x+8=18
10x=10
x=1
so your answer is x=1 and y=4 or (1,4)
