The centre of the circle whose radius is 5 and which touches the circle `x^(2)+y^(2)-2x-4y-20=0` at `(5,5)` is

Find the equation of the circle whose radius is 5 and which touches the circle x^(2)+y^(2)-2x-4y-20=0 externally at the point (5,5).

Centre of the circle whose radius is 3 and which touches internally the circle x^(2)+y^(2)-4x-6y-12=0 at the point (-1 -1) is

Difference in values of the radius of a circle whose center is at the origin and which touches the circle x^(2)+y^(2)-6x-8y+21=0 is

The tangent to the circle x^(2)+y^(2)=5 at a point (a,b) , touches the circle x^(2)+y^(2)-8x+6y+20=0 at (3,-1) .The values of a and b are

Find the centre and radius of the circle x^(2)+y^(2)+2x-4y-4=0