Question 53279: Can you please show me how to solve the system by addition?
x+y=9
x-y=9
Thank you Found 2 solutions by Nate, stanbon:Answer by Nate(3500) (Show Source):
You can put this solution on YOUR website! 1st: x+y=9
2nd: x-y=9
Add the two equations to get:
3rd: 2x=18
x=9
Substutute that into 1st to solve for y, as follows:
9+y=9
y=0
Check the answer in 2nd.
x-y=9
9-0=9
9=9
Cheers,
Stan H.
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