SOLUTION: what are the steps when solving an equation using subatitution

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Question 117666: what are the steps when solving an equation using subatitution
Answer by checkley71(8403) About Me  (Show Source):
You can put this solution on YOUR website!
x+2y=7 & 3x-2y=-3
Now we have:
x+2y=7 or x=-2y+7
Now substitute (-2y+7) for x in the other equation & solve for y
3(-2y+7)-2y=-3
-6y+21-2y=-3
-8y=-3-21
-8y=-24
y=-24/-8
y=3 answer.
x+2*3=7
x+6=7
x=7-6
x=1 answer.
proof
3*1-2*3=-3
3-6=-3
-3=-3