note that the equation of the circle is
(x-h)² +(y-k)² =r²
where centre is (h,k)
the equation of the circle based on the information given
(x-3)² +(y-4)² =r²
and the point on the circle (3,-2)
substitute into the equation
(3-3)² +(-2-4)² =r²
r=6 or r=-6
since r is radius, we reject r=-6 since radius must be nonnegative.
the radius is 6
