parallelogram ABCD
AC and BD are diagonals
AC and BD intersect at point E
AB is parallel to CD | opposite sides of a parallelogram are parallel
AB = CD | are congruent opposite sides of a parallelogram
angle BAC = angle DCA |interior angles of parallel lines
angle ABD = angle CDB |interior angles of parallel lines
Triangle ABE = Traingle CDE | ASA
EA = EC | corresponding sides of congruent triangles are congruent.
E bisects AC| AE = EC
hope its help