SOLUTION: how do you do 2x-y=2 -5x+4y=-2 in elimination method

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Question 563016: how do you do 2x-y=2
-5x+4y=-2 in elimination method
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
(1) +2x+-+y+=+2+
(2) +-5x+%2B+4y+=+-2+
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Multiply both sides of (1) by +4+
and add the equations
(1) +8x+-+4y+=+8+
(2) +-5x+%2B+4y+=+-2+
+3x+=+6+
+x+=+2+
Plug this back into (1) or (2)
(1) +2%2A2+-+y+=+2+
(1) +4+-+y+=+2+
(1) +-y+=+2+-+4+
(1) +-y+=+-2+
(1) +y+=+2+
The solution is (2,2)
Here's the plot of the 2 lines:
+graph%28+400%2C+400%2C+-5%2C+5%2C+-5%2C+5%2C+2x+-+2%2C+%285%2F4%29%2Ax+-+2%2F5%29+