SOLUTION: X+y=4 X-y=5

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Question 835469: X+y=4
X-y=5
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
Add the equations together,
x%2By%2Bx-y=4%2B5
2x=9
x=9%2F2
Now use either equation to solve for y
x%2By=4
9%2F2%2By=4
y=-1%2F2