1. The problem statement, all variables and given/known data In cyclic quadrilateral ABCD with diagonals intersecting at E, we have AB=5, BC=10, BE=7, and CD=6. Find CE. 2. Relevant equations Ptolemy's Theorem: The product of the measures of its diagonals is equal to the sum of the products of the measures of the pairs of opposite sides. 3. The attempt at a solution I drew the picture and that's as far as I got.