SOLUTION: graph the circle x^2 + y^2 -4x + 8y = 24

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Question 285163: graph the circle
x^2 + y^2 -4x + 8y = 24
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
Complete the square in x and y.
x%5E2+%2B+y%5E2+-4x+%2B+8y+=+24
x%5E2-4x+%2B+y%5E2%2B8y+=+24
%28x%5E2-4x%2B4%29+%2B+%28y%5E2%2B8y%2B16%29+=+24%2B4%2B16
%28x-2%29%5E2+%2B+%28y%2B4%29%5E2+=+44
Compare to the general equation for a circle centered at (h,k) with a radius R:
%28x-h%29%5E2%2B%28y-k%29%5E2=R%5E2
This circle is centered at (2,-4) and has a radius of sqrt%2844%29=2%2Asqrt%2811%29.