The difference between the radii of the largest and smallest circles which have their centres on the circumference of the circle `x^2 + y^2 + 2x + 4y -4 = 0` and passes through point (a,b) lying outside the circle is :

Find the radius and centre of the circle of the circle x^(2) + y^(2) + 2x + 4y -1=0 .

Find the equation of the circle concentric with the circle x^2 +y^2 - 4x - 6y-9=0 and passing through the point (-4, -5)

Let r _(1) and r _(2) be the radii of the largest and smallest circles, respectively, which pass through the point (–4,1) and having their centres on the circumference of the circle x ^(2) + y ^(2) + 2x + 4y - 4 =0 . If (r _(1))/(r _(2)) = a + b sqrt2. then a + b is equal to .

Find the equation of the circle concentric with the circle x^(2) + y^(2) + 4x + 4y + 11 = 0 and passing through the point ( 5, 4).

Equation of the circle concentric with the circle x^(2)+y^(2)-3x+4y-c=0 and passing through the point [(-1,-2) is

Find the equation of the circle concentric With the circle x^(2) + y^(2) - 4x - 6y - 9 = 0 and passing through the point ( -4, -5).

find the equation of the tangents to the circle x^(2)+y^(2)-2x-4y-20=0 which pass through the point (8,1)

The locus of the centre of the circle which bisects the circumferences of the circles x^(2)+y^(2)=4&x^(2)+y^(2)-2x+6y+1=0 is :

If 'P' is any point on the circumference of the circle x^(2) + y^(2) - 4x - 4y -8 =0 , then the perpendicular distance of the tangent at P from the centre of the circle is