Let equation of circle is
x2+y2+2gx+2fy+c=0
Differentiating above equation w.r.t x we get,
⇒dxdy=−(2y+2f)(2x+2g)
Now, comparing with dxdy=bx+cy+aax−by+a
We get, b=0,a=−2,c=2
⇒−2g=−2⇒g=1
Also, 2f=−2
So, f=−1
Now circle will be
x2+y2+2x−2y+c=0
its passes through (2,5)
which will give c=−23
so circle will be x2+y2+2x−2y−23=0
centre C=(−1,1)
and radius 5
Now P is (11,6)
So minimum distance of P from circle will be =(11+1)2+(6−1)2−5
=13−5=8