Question 3
Let $A, B, C, D, E$ be points such that $A B C D$ is a cyclic quadrilateral and $A B D E$ is a parallelogram. The diagonals $A C$ and $B D$ intersect at $S$ and the rays $A B$ and $D C$ intersect at $F$. Prove that $\angle A F S=\angle E C D$.