SOLUTION: 2x-3y=-1 Y=x-1 Slove system by subsitution

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Question 700524: 2x-3y=-1
Y=x-1
Slove system by subsitution
Answer by Stitch(470) About Me  (Show Source):
You can put this solution on YOUR website!
Given:
Equation 1: 2X+-+3Y+=+-1
Equation 2: Y+=+X+-+1
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Since we know what Y is equal to, plug (X - 1) into equation 1 for Y
Equation 1: 2X+-+3Y+=+-1
2X+-+3%2A%28X+-+1%29+=+-1
Multiply through
2X+-+3X+%2B+3+=+-1 Note that the two negative sign canceled out to give us positive 3
Now combine like terms
-X+%2B+3+=+-1
Subtract 3 from both sides
-X+=+-4
Divide both sides by -1
highlight%28X+=+4%29
Now plug 4 into equation 2 for X
Equation 2: Y+=+X+-+1
Y+=+%284%29+-+1
highlight_green%28Y+=+3%29