SOLUTION: solve the system by elimination method x+8y=-16 4x+9y=-18

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Question 84941: solve the system by elimination method x+8y=-16
4x+9y=-18

Answer by checkley75(3666) About Me  (Show Source):
You can put this solution on YOUR website!
x+8y=-16 now multiply this equation by -4 & add it to the second equation thus:
-4x-32y=64
4x+9y=-18
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-23y=46
y=46/-23
y=-2 answer. now substitute 2 for y & solve for x thus:
x+8*-2=-16
x-16=-16
x=-16+16
x=0 answer.
proof
4*0+9-2=-18
-18=-18