parallelogram properties 1.>Each diagonal divides it into two congruent triangles. 2.>Diagonals need not bisect angles at the vertices. I dont understand these two properties. In property 1: what does congruent triangles means ? i am not familiar with this term...is this same as "similar triangle" ? please explain. In property 2: it says, diagonal does not bisect vertices. If this is so , that means two halves of the triangle does not have the same area when a diagonal divides the parallelogram......am i correct ? Or, in other words ,...In mathematical term, if ABCD is the parallelogram and if BD is the diagonal....then Area ABD =! Area BDC ......is this correct ?