Question 114
The bisector of the angle $CAB$ of the triangle $ABC$ intersects the side $CB$ at $L$. The point $D$ is the foot of the perpendicular from $C$ to $AL$ and the point $E$ is the foot of the perpendicular from $L$ to $AB$. The lines $CB$ and $DE$ meet at $F$.
Prove that $AF$ is an altitude of the triangle $ABC$.
Prove that $AF$ is an altitude of the triangle $ABC$.