SOLUTION: what does the x any y equal using substitution in both equations 2x+y=0; x+3y=-56

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Question 750513: what does the x any y equal using substitution in both equations 2x+y=0; x+3y=-56
Answer by checkley79(3341) About Me  (Show Source):
You can put this solution on YOUR website!
2x+y=0 or y=-2x
x+3y=-56
x+3(-2x)=-56
x-6x=-56
-5x=-56
x=-56/-5
x=11.2 ans.
y=-2*11.2
y=-22.4 ans.
Proof:
11.2+3*-22.4=-56
11.2-67.2=-56
-56=-56