You can put this solution on YOUR website! Graph the following conic section
x^2+8x+y^2-4y=16
complete the square
(x^2+8x+16)+(y^2-4y+4)=16+16+4
(x+4)^2+(y-2)^2=36
This is an equation of a circle with center at (-4,2) with radius=6
see graph of circle below:
(36-(x+4)^2)^.5+2