SOLUTION: x^2+y^2=24 y=2x+3

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Question 359472: x^2+y^2=24
y=2x+3
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
1.x%5E2%2By%5E2=24
2.y=2x%2B3
Substitute eq. 2 into eq. 1 and solve for x.
x%5E2%2B%282x%2B3%29%5E2=24
x%5E2%2B4x%5E2%2B12x%2B9=24
5x%5E2%2B12x%2B9=24
5x%5E2%2B12x-15=0
Use the quadratic formula,
x+=+%28-12+%2B-+sqrt%28+12%5E2-4%2A5%2A%28-15%29+%29%29%2F%282%2A5%29+
x+=+%28-12+%2B-+sqrt%28+144%2B300+%29%29%2F10+
x+=+%28-12+%2B-+sqrt%28+444+%29%29%2F10+
x+=+%28-12+%2B-+2%2Asqrt%28+111+%29%29%2F10+
x+=+%28-6+%2B-+sqrt%28+111+%29%29%2F5
Then from eq. 2,
y=2x%2B3
y=%28-12+%2B-+2%2Asqrt%28+111+%29%29%2F5%2B15%2F5
y=%283+%2B-+2%2Asqrt%28+111+%29%29%2F5
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(x%5B1%5D,y%5B1%5D)= (+%28-6+%2B+sqrt%28+111+%29%29%2F5,+%28-3+%2B+2%2Asqrt%28+111+%29%29%2F5)
(x%5B2%5D,y%5B2%5D)=(+%28-6+-+sqrt%28+111+%29%29%2F5,+%28-3+-+2%2Asqrt%28+111+%29%29%2F5)
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