Find the angle between the circles
`x^2 + y^2 + 4x - 14y + 28 = 0` and
`x^2 + y^2 + 4x - 5 = 0`

Find the transverse common tangents of the circles x^(2) + y^(2) -4x -10y + 28 = 0 and x^(2) + y^(2) + 4x - 6y + 4= 0.

If the angle between the circles x^(2) +y^(2) +4x - 5 = 0 and x^(2) +y^(2) +2lambda y- 4 = 0 "is" (pi)/(3), " then " lambda =

Find the transverse common tangents of the circles x^(2) + y^(2) -4x -10y + 28 = 0 and x^(2) + y^(2) + 4x - 6y + 4 =0.

The angle between the circles x^2+y^2-2x-4y+3=0 and x^2+y^2-4x-6y+11=0 is

The angle between the circles x^2+y^2-2x-4y+3=0 and x^2+y^2-4x-6y+11=0 is

The angle between the circles x^2+y^2+4x+8y+18=0 and x^2+y^2+2x+6y+8=0 is

The angle between the circles x^2+y^2+4x+8y+18=0 and x^2+y^2+2x+6y+8=0 is

Find the equation of the circle the end points of whose diameter are the centres of the circle : x^2 + y^2 + 6x - 14y=1 and x^2 + y^2 - 4x + 10y=2 .

Find the equation of the circle the end points of whose diameter are the centres of the circle : x^2 + y^2 + 6x - 14y=1 and x^2 + y^2 - 4x + 10y=2 .