Parallelogram

Definition

A parallelogram is a flat geometric shape having four sides with two pairs of opposite parallel sides that are equal in length.

Properties

1. Both pairs of opposite sides are equal; in ▱ABCD, AB = CD and BC = DA
2. Both pairs of opposite sides are parallel; so AB∥ CD and AD ∥ BC
3. Opposite angles are of equal measure; so ∠DAB = ∠BCD and ∠ABC = ∠CDA
4. Adjacent angles add up to 180°; ∠DAB +∠ABC = 180°, ∠ABC + ∠BCD = 180°, ∠BCD + ∠CDA = 180°, and ∠CDA + ∠DAB = 180°
5. Diagonals bisect each other; here AC and BD bisect each other

Formulas

Area

The total space enclosed by the parallelogram. The formula is given below:

Area (A) = b × h, here b = base, h = height

Perimeter

The total distance covered around the edge of the parallelogram. The formula is given below:

Perimeter (P) = 2(a + b), here a & b are adjacent sides

Types

Based on their properties, parallelogram can be of three special types:

1. Rhombus

2. Rectangle

3. Square