If the circles `x^2+y^2+2ax+c=0 and x^2+y^2+2by+c=0` touch each other, then find the relation between `a, b and c`.

If one of the circles x^2+y^2+2ax+c=0 and x^2+y^2+2bx+c=0 lies within the other, then

The two circles x^(2)+y^(2)-cx=0 and x^(2)+y^(2)=4 touch each other if:

The circles x^(2)+y^(2)+2x-2y+1=0 and x^(2)+y^(2)-2x-2y+1=0 touch each other

If two circles and a(x^2 +y^2)+bx + cy =0 and p(x^2+y^2)+qx+ry= 0 touch each other, then

If a^2+b^2+c^2-a b-b c-c a=0, then find the relation between a,b and c

If two circles x^2 + y^2 + ax + by = 0 and x^2 + y^2 + kx + ly = 0 touch each other, then (A) al = bk (B) ak = bl (C) ab = kl (D) none of these

If the circles x^2+y^2-9=0 and x^2+y^2+2ax+2y+1=0 touch each other, then a is -4/3 (b) 0 (c) 1 (d) 4/3

If the circles x^2+y^2-9=0 and x^2+y^2+2a x+2y+1=0 touch each other, then alpha is (a) -4/3 (b) 0 (c) 1 (d) 4/3

Prove that the circle x^2 + y^2 =a^2 and (x-2a)^2 + y^2 = a^2 are equal and touch each other. Also find the equation of a circle (or circles) of equal radius touching both the circles.

Prove that the circle x^2 + y^2 =a^2 and (x-2a)^2 + y^2 = a^2 are equal and touch each other. Also find the equation of a circle (or circles) of equal radius touching both the circles.