Question 24811
Starting with the standard form of the equation for a circle with centre at (h, k) and radius, r:
{{{(x - h)^2 + (y - h)^2 = r^2}}}
You are given the radius, so {{{r = 3}}} and {{{r^2 = 9}}}
The circle is tangent to both the x-axis and the y-axis in quadrant II, so by inspection you can see that the centre is located at (-3, 3) so h = -3 and k = 3.
The equation therefore is:
{{{(x + 3)^2 + (y - 3)^2 = 9}}}