Distance Formula

The distance between two points $\left(3, 5\right)$ and $\left(5, 7\right)$ will be 

If the distance between the points $\left(2, 3\right)$ and $\left(4, 1\right)$ is $k\sqrt{k}$. Find the value of $k$.

Find the point on the X-axis which is equidistant from $(2, –5)$ and $(–2, 9)$.