SOLUTION: x^2+y^2=22 x+y=1

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Question 685215: x^2+y^2=22
x+y=1
Answer by pmatei(79) About Me  (Show Source):
You can put this solution on YOUR website!
From the second equation:
x+=+1-y
Replace x in the first equation:
%281-y%29%5E2+%2B+y%5E2+=+22
1+-+2y+%2B+y%5E2+%2B+y%5E2+=+22
2y%5E2+-2y+-21+=+0
y+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+
y+=+%282+%2B-+sqrt%28%28-2%29%5E2-4%2A2%2A%28-21%29%29%29%2F%282%2A2%29
y+=+%281%2F2+%2B-+sqrt%2843%29%2F2%29
First solution: x=1%2F2-sqrt%2843%29%2F2 , y=1%2F2%2Bsqrt%2843%29%2F2.
Second solution: x=1%2F2%2Bsqrt%2843%29%2F2 , y=1%2F2-sqrt%2843%29%2F2.