Parallelograms
A parallelogram is a quadrilateral whose opposite sides are parallel.
The defining property for a parallelogram is that it is a quadrilateral whose opposite sides are parallel. Many other properties follow from this. The most significant feature of the figure is that for either pair of opposite sides, the other two sides and the diagonals are transversals.
Thus, the theory of parallel lines and transversals may be used to prove properties of parallelograms. This theory and that for congruent triangles provide the needed tools for study of parallelograms.
Find out more about parallelograms by reading the explanation below.
Practice: Identify and use the properties of parallelograms by answering the exercises below.