Let
be a convex pentagon with all five sides equal in length. The diagonals
and
meet in
with
. Prove that
has a pair of parallel sides.
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Let $ABCDE$ be a convex pentagon with all five sides equal in length. The diagonals $AD$ and $EC$ meet in $S$ with $\angle ASE = 60^\circ$. Prove that $ABCDE$ has a pair of parallel sides.
Školjka