Question 207924
(0,0)
{{{graph (600,600,-5,5,-5,5,sqrt(9-x^2),-sqrt(9-x^2))}}}
the formula of a circle is:
{{{(x-h)^2 + (y-k)^2 = r^2}}}
this formula has h = 0 and k = 0
this is a circle with the center at the origin.
the radius of the circle = 3
(h,k) is the center of the circle.
r^2 is the radius squared of the circle.