Let \( ABCDV \) be a rectangle based-pyramid, where \( V \) is its apex, and let \( XY \) be a line where:
\begin{align*}
X&\text{ lays on a ray }BA\text{ and }|BA|=|AX|,\\
Y&\text{ lays on the height }SV\text{ and }|SY|=|YV|,\\
S&\text{ is the centre of the pyramid base}
\end{align*}
(see the picture). The points of intersection of the line \( XY \) with the surface of the pyramid lay: