SOLUTION: X+y=1 X-2y=4

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Question 1033954: X+y=1
X-2y=4
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
(1) +x+%2B+y+=+1+
(2) +x+-+2y+=+4+
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Multiply both sides of (1) by +2+
and add the equations
(1) +2x+%2B+2y+=+2+
(2) +x+-+2y+=+4+
-------------------
+3x+=+6+
+x+=+2+
and
(1) +x+%2B+y+=+1+
(1) +2+%2B+y+=+1+
(1) +y+=+-1+
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The solution is:
( 2, -1 )
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Here's the plot:
+graph%28+400%2C+400%2C+-6%2C+6%2C+-6%2C+6%2C+-x+%2B+1%2C+%281%2F2%29%2Ax+-+2+%29+