<PRE><B>Question 16313</B>
There are several ways to do this problem (linear combination, substitution, graphing).  The easiest is by linear combination.  You are going to subtract the two equations.
  x+y=12
-(x-y=2)  Put the common terms over each other like a subtraction problem.
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  x+y=12
 -x+y=-2  Distribute the negative to both sides of equation
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 0x+2y=10  Combine like terms.

2y=10
2y/2=10/2
y=5</PRE>