The points of intersection of circles ${x^2} + {y^2} = 2ax$ and ${x^2} + {y^2} = 2by$ are
$(0, 0)$, $(a, b)$
$(0, 0)$, $\left( {\frac{{2a{b^2}}}{{{a^2} + {b^2}}},\frac{{2b{a^2}}}{{{a^2} + {b^2}}}} \right)$
$(0, 0)$, $\left( {\frac{{{a^2} + {b^2}}}{{{a^2}}},\frac{{{a^2} + {b^2}}}{{{b^2}}}} \right)$
None of the above
The centre of the smallest circle touching the circles $x^2 + y^2- 2y - 3 = 0$ and $x^2+ y^2 - 8x - 18y + 93 = 0$ is :
The number of circles touching the line $y - x = 0$ and the $y$-axis is
The circles $x^2 + y^2 + 2x -2y + 1 = 0$ and $x^2 + y^2 -2x -2y + 1 = 0$ touch each other :-
The number of common tangents to the circles ${x^2} + {y^2} = 1$and ${x^2} + {y^2} - 4x + 3 = 0$ is
The equation of the circle through the point of intersection of the circles ${x^2} + {y^2} - 8x - 2y + 7 = 0$, ${x^2} + {y^2} - 4x + 10y + 8 = 0$ and $(3, -3)$ is