Consider that the equation of a circle with center (h,k) and radius 'r' units, is given by,
Observe the given diagram carefully.
The center of the circle lies at (-2,1),
The radius of the circle is the distance of any point on the circle from the center. Since the point (3,0) lies on the circle, the radius is calculated as,
Substitute the values in the standard equation of circle,
Thus, the equation of the given circle is,