If the circle x2+y2+2ax+2by+c=0, then find the centre and the radius the circle.
The two circles x2+y2+2ax+c=0 and x2+y2+2by+c=0 touch if 1a2+1b2=
If the circles x2+y2+2ax+c=0 and x2+y2+2by+c=0 touch each other, then
(a,b) is the mid point of the chord ¯AB of the circle x2+y2=r2. The tangent at A,B meet a C. then area of ΔABC