let centre (x0,y0),radius requation of circle C:(x-x0)^2+(y-y0)^2 =r^2(x0,y0) is on Lx0-y0+2=0x0=y0-2 (1)A is on Cx0^2+(y0+6)^2 =r^2 (2)B is on C(x0-2)^2+(y0+4)^2 =r^2 (3)(1)=(2)x0^2+(y0+6)^2 = (x0-2)...