Second hint to puzzle 63: Cyclic hexagon
Rearrange the order of the sides of the hexagon to 2, 7, 11, 2, 7, 11. Since the two sets of sides, {2, 7, 11}, are congruent, each can be inscribed in a semicircle. Now apply Ptolemy's Theorem.
Rearrange the order of the sides of the hexagon to 2, 7, 11, 2, 7, 11. Since the two sets of sides, {2, 7, 11}, are congruent, each can be inscribed in a semicircle. Now apply Ptolemy's Theorem.