A. √52

B. √2

C. √13

D. √10

If one end of the diameter of the circle x^{2}+y^{2}-6x+4y-12=0 is (7, -5), then the other end of the diameter is

Polar of the origin w.r.t the circle x^{2}+y^{2}+2ax+2by+c=0 touches the circle x^{2}+y^{2}=r^{2} if

The circle orthogonal to the three circles x^{2}+y^{2}+a_{i}x+b_{i}y+c=0, i=1, 2, 3 is

The coaxal system having limiting points (2,3), (-3, 2) is

If the two circles (x-1)^{2}+(y-3)^{2}=r^{2} and x^{2}+y^{2}-8x+2y+8=0 intersect in two distinct points, then