SOLUTION: x^2 + xy = 7 x + 2y = 5 slove for x and y

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Question 250930: x^2 + xy = 7
x + 2y = 5
slove for x and y
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
1.x%5E2+%2B+xy+=+7
2.x+%2B+2y+=+5
From 2,
2y=5-x
y=%281%2F2%29%285-x%29
xy=%281%2F2%29%285x-x%5E2%29
Substitute into 1,
1.x%5E2+%2B+xy+=+7
x%5E2+%2B+%281%2F2%29%285x-x%5E2%29+=+7
2x%5E2+%2B+5x-x%5E2+=+14
x%5E2%2B5x-14=0
%28x%2B7%29%28x-2%29=0
Two solutions:
+x%2B7=0+
+x=-7
+2y=5-x=5-%28-7%29=12
+y=6
(+-7,+6)
.
.
.
+x-2=0
+x=2
+2y=5-x=5-2=3
+y=3%2F2
(+2,+3%2F2)
Graphically, here is the solution also,