Given the graph of the circle
To write the equation of the circle , we need to find the radius and the coordinates of the center
As shown in the figure :
The center of the circle = (h,k) = ( 7 , 5 )
And the radius of the circle = r = 3
The general equation of the circle is :

Substitute with the values of h, k and r :
So, the equation of the given circle is :
