SOLUTION: Solve this system of equations with the substitution method Y=3x - 2 Y=-1/2x + 5

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Question 5043: Solve this system of equations with the substitution method
Y=3x - 2
Y=-1/2x + 5
Answer by rapaljer(4671) About Me  (Show Source):
You can put this solution on YOUR website!
Y=3x - 2
Y=-1/2x + 5

Substitution method means to substitute x or y from one equation into the other equation. In this case, since both equations are in "Y= " format, set them equal to each other:
3x - 2 = -1/2x + 5

Some people don't like fractions, so to clear the fractions, multiply both sides by 2:
2%2A3x+-+2%2A+2+=+2%2A%28-1%2F2%29x+%2B+2%2A5
6x+-+4+=+-x+%2B+10

Add +x from each side, and add +4 to each side to get all x terms to the left side and the number terms to the right side:
6x+%2Bx++-+4+=+-x+%2B+x+%2B+10
7x+-+4+=++10
7x+-+4+%2B+4+=++10+%2B+4
+7x+=+14
+x+=+14%2F7+=+2

If x+=+2, substitute into the first equation:
Y+=+3x+-+2
Y=3%282%29+-+2
Y+=+6+-+2
Y+=+4

Check in the second equation:
Y=-1/2x + 5
+4+=%28-1%2F2%29%2A%282%29+%2B+5
+4+=+-1+%2B+5+

R^2 at SCC