A Parallelogram is a flat shape with opposite sides parallel and equal in length.

| and || show equal sides

  • Opposite sides are parallel
  • Opposite sides are equal in length
  • Opposite angles are equal (angles "a" are the same, and angles "b" are the same)
  • Angles "a" and "b" add up to 180°, so they are supplementary angles.

Area of a Parallelogram

The Area is the base times the height:

Area = b × h

(h is at right angles to b)


A parallelogram has a base of 9 m and is 2 m high, what is its Area?

Area = 9 m × 2 m = 18 m²

Perimeter of a Parallelogram

The Perimeter is the distance around the edges.

The Perimeter is 2 times the (base + side length):

Perimeter = 2(b+sl)


 A parallelogram has a base of 24 cm and a side length of 12 cm, what is its Perimeter?

Perimeter = 2 × (24 cm + 12 cm) = 2 × 36 cm = 72cm

Diagonals of a Parallelogram

The diagonals of a parallelogram bisect each other.

In other words the diagonals intersect each other at the half-way point.