Question 702242: 2x-y=-4
-3x+y=-9
Answer by AFKeying(5)   (Show Source):
You can put this solution on YOUR website! Think of this kind of problem like doing addition (vertically) just with equations.
The goal is to get one of the variables to cancel, you can see the y's will cancel, so add the x's, the y's and the constants.
2x-y=-4
-3x+y=-9
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-x = -13 (divide by -1 to get x by itself)
x = 13
Now that you know what x is, plug x back into one or both of the equations to solve for y.
for the sake of argument, I'll do both.
2(13)-y=-4
26-y=-4
-y=-4-26
-y=-30
y=30
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-3(13)+y=-9
-39+y=-9
y=-9+39
y=30
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