Question 264309
Hello, 
The best way to do this is multiply the equation by -1 so to cancel out the y's
-2x(-1) + y(-1) = 1(-1) which gives us:
2x-y=-1 Now add this to the second equation: 
3x + y = 1
And we get:
5x=0 Divide both sides by 5 and we get:
x=0
Now plug this into either original equation to find out "y"
-2(0) + y = 1 Do the calculations and we have:
y=1
There we go the solutions will work in either equation now. 
RJ 
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