I. ` x^(2) + 4x+4 = 0`
II. ` y^(2) - 8y + 16 = 0`

I. x^(2) + 4x = 21 II y^(2) - 6y + 8 = 0

Two circles x^(2) + y^(2) - 2x - 4y = 0 and x^(2) + y^(2) - 8y - 4 = 0

Two circles x^(2) + y^(2) -2kx = 0 and x^(2) + y^(2) - 4x + 8y + 16 = 0 touch each other externally.Then k is

(i) 7x^(2) + 16x - 15 = 0 (ii) 5y^(2)+ 8y - 21 = 0

Prove that the centres of the circle x^(2) + y^(2) - 4x - 2y + 4 = 0, x^(2) + y^(2) - 2x - 4y + 1 = 0 and x^(2) + y^(2) + 2x - 8y + 1 = 0 are collinear. More over prove that their radii are in geometric pregression.

The point of tangency of the circles x^2+ y^2 - 2x-4y = 0 and x^2 + y^2-8y -4 = 0 , is

The point of tangency of the circles x^2+ y^2 - 2x-4y = 0 and x^2 + y^2-8y -4 = 0 , is

The point of tangency of the circles x^2+ y^2 - 2x-4y = 0 and x^2 + y^2-8y -4 = 0 , is