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

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Question 931954: Graph the circle
x^2+y^2-8x+4y=-4
Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
Use Completing The Square to put the equation into standard form, from which you can directly read the radius and center point, and graph accordingly.

Standard Form for a circle is %28x-h%29%5E2%2B%28y-k%29%5E2=r%5E2;
r is the radius, and (h,k) is the center point.


Start as x%5E2-8x%2By%5E2%2B4y=-4;
and the necessary term for x is %28-8%2F2%29%5E2=16; and the necessary term for y is %284%2F2%29%5E2=4.
x%5E2-8x%2B16%2By%5E2%2B4y%2B4=-4%2B16%2B4, and if this makes sense to you, good! Keep going until finished...