Question 233553
How do I solve for addition x-2y=-1, -x+5y=4 when I don't have numbers for x.
I tried x-2y=-1 (x=2y+-1) x=-3, 
solve for addition x-2y=-1
-x+5y=4
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I don't know what "solve for addition" means, but
+x-2y=-1
-x+5y=4
---------- Add the equations
3y = 3
y = 1
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x-2y = -1
x-2 = -1
x = 1