Given equation is
x2+y2−4x+6y−51=0
⇒x2+y2−4x+6y−(64+9−4)=0
⇒(x2−4x+4)+(y2+6y+9)−64=0
⇒(x−2)2+(y+3)2=64
On comparing the given equation with the standard equation of circle i.e., (x−h)2+(y−k)2=r2 we get, h = 2 and k = -3.
So, the centre of the circle is (2,-3).