Question 75
In a rectangular system $xOy$ the graph of the function $f: \mathbb{R} \rightarrow \mathbb{R}$, $f(x) = x^{2}$ is drawn. The ordered triple $B, A, C$ has distinct points on the parabola, the point $D \in BC$ such that the straight line $AD$ is parallel to the axis $Oy$ and the triangles $BAD$ and $CAD$ have the areas $s_{1}$ and $s_{2}$ respectively. Find the length of the segment $[AD]$.