Question

how to solve 2x-y=17;x-y=10

Answer 1

the answer is that y is equal to -3 and x is equal to 7 
2x-y=17
-2(x-y)=10 )
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2x-y=17
-2x+2y=-20
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y=-3

x-y=10 
x-(-3)=10
x+3=10
 -3   -3
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x=7