SOLUTION: y=3x+2 3x+y=1

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Question 1060139: y=3x+2
3x+y=1

Answer by math_helper(2461) About Me  (Show Source):
You can put this solution on YOUR website!

Since you have 2 equations and 2 unknowns, the first thing is to try to solve for one of the variables. So long as the two equations are "linearly independent" (or not linearly-dependent) there will be a solution.
Linearly dependent means one equation can be re-arranged to exactly match the other (in essence, if they only "look" like two different equations but are in fact the same). Ok, enough on that…

+y=3x%2B2+ (1)
+3x%2By+=+1+ (2)
(1) conveniently expresses y as a function of x, so let's substitute "3x+2" from (1) for "y" in (2):
+3x+%2B+%283x%2B2%29+=+1+ (substituted "3x+2" for "y")
++6x+%2B+2+=+1+
+++6x+=+-1+
++x+=+-1%2F6+
If x=-1%2F6 we can plug into (1) to get +y=3%28-1%2F6%29%2B2+=+-%281%2F2%29%2B%284%2F2%29+=+3%2F2+

Ans: +x=-1%2F6+ and +y=3%2F2+

Check:
(1) Does 3/2 = (3*(-1/6) + 2)?
3/2 = (-3/6)+(12/6)
3/2 = 9/6
3/2 = 3/2 (ok)
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(2) Does 3(-1/6) + (3/2) = 1 ?
-(1/2) + (3/2) = 1 ?
2/2 = 1 (ok)