This equation is in what’s called general from. To convert to standard form (the form needed to graph: (x-h)^2+(y-k)^2), you would need to first put the x’s next to each other any the y’s next to each other, also put the 18 on the other side.
1. “x^2+6x+y^2+10y=-18
2. Complete the square: (b/2)*2
(x^2+6x+9)+(y^2+10y+25)=-18
(x+3)^2+(y+5)^2=-18
Now you have a form where you can tell the center and the radius.
