SOLUTION: Solve by graphing. x + y = 3 x - y = 1 I did: x + y = 3 y = -x + 3 m = -1, 6 = 3 x - y = 1 -y = -x + 1 m = -1, 6 = 1 on my graph they coincided

Algebra ->  Algebra  -> Graphs -> SOLUTION: Solve by graphing. x + y = 3 x - y = 1 I did: x + y = 3 y = -x + 3 m = -1, 6 = 3 x - y = 1 -y = -x + 1 m = -1, 6 = 1 on my graph they coincided      Log On

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Question 67796: Solve by graphing.
x + y = 3
x - y = 1
I did:
x + y = 3 y = -x + 3 m = -1, 6 = 3
x - y = 1 -y = -x + 1 m = -1, 6 = 1
on my graph they coincided with each other instead of intersecting which is how the answer reads. (2,1)
Where did I go wrong?
Thanks a lot. Kyle
Answer by checkley71(8403) About Me  (Show Source):
You can put this solution on YOUR website!
X+Y=3
Y=-X+3
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X-Y=1
-Y=-X+1
Y=X-1 this is where you made your mistake. you neglected to change -y to +y by multiplying the equation by -1.
also you have a 6 instead of a y in your answer.
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graph%28+300%2C+200%2C+-6%2C+5%2C+-5%2C+5%2C+y+=+-x+%2B3%2C+y+=+x+-1%29 (graph 300x200 pixels, x from -6 to 5, y from -5 to 5, of TWO functions y = -x +3, y = x -1).