Originally Posted by BetterSense You can verify that it's a rectangle by comparing the diagonal measurements. They should be the same. Let's assume that we have the trapezium ABCD and AB, CD are the parallel sides. If angles A=B and C=D, then the diagonals AC, BD will be equal!

Last edited by Anon Ymous; 08-30-2009 at 01:30 PM. Click to view previous post history.