A circle ${C_1}$ of radius $2$ touches both $x$ – axis and $y$ – axis. Another circle ${C_2}$ whose radius is greater than $2$ touches circle ${C_1}$ and both the axes. Then the radius of circle ${C_2}$ is

The value of $\lambda $, for which the circle ${x^2} + {y^2} + 2\lambda x + 6y + 1 = 0$, intersects the circle ${x^2} + {y^2} + 4x + 2y = 0$ orthogonally is

The circle passing through point of intersection of the circle $S = 0$ and the line $P = 0$ is

The equation of radical axis of the circles $2{x^2} + 2{y^2} – 7x = 0$ and ${x^2} + {y^2} – 4y – 7 = 0$ is

Two orthogonal circles are such that area of one is twice the area of other. If radius of smaller circle is $r$, then distance between their centers will be –