Question 37637
You can start with the general form of the equation for a circle whose center is at (h, k) and whose radius is r:
{{{(x-h)^2+(y-h)^2 = r^2}}}

Applying this to your problem, we first have to find the length of the radius, r. I assume that the coordinates that you have given for the radius are the coordinates of the end-point of the radius.  Since the radius of a circle begins at the center of the circle, we need to find the distance between the center (6, 6) and the end-point (-4, 3) using the distance formula:
{{{d=sqrt((x2-x1)^2+(y2-y1)^2)}}}
{{{d=sqrt((-4-6)^2+(3-6)^2)}}}
{{{d=sqrt((-10)^2+(-3)^2)}}}
{{{d=sqrt(100+9)}}}
{{{d=sqrt(109)}}} This is the radius.
But we want {{{r^2}}}
{{{r^2 = 109}}}

Now for the circle:

{{{(x-6)^2+(y-6)^2 = 109}}}