SOLUTION: How do I solve Solve by addition 2x + y = 3 x - y =3

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Question 177561: How do I solve
Solve by addition
2x + y = 3
x - y =3
Found 2 solutions by Fombitz, stanbon:
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
Add the two equations together and solve for x.
Then go back and solve for y.
1.2x%2By=3
2.x-y=3
.
.
.
%282x%2By%29%2B%28x-y%29=3%2B3
3x=6
highlight%28x=2%29
Then from eq. 2,
2.x-y=3
2-y=3
-y=1
highlight%28y=-1%29

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
Solve by addition
2x + y = 3
x - y =3
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Modify the equations:
2x + y = 3
-2x +2y = -6
-------------------
Add to get:
3y = 3
y = 1
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Substitute to solve for "x":
x-1 = 3
x = 4
----------------
Ans: (4,1)
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Cheers,
Stan H.