What is Parallelogram?
A parallelogram is a special type of quadrilateral that has equal and parallel opposite sides.
The given figure shows a parallelogram ABCD which as AB parallel to CD and AD parallel to BC.
Also, AD = BC and AB = CD.
The opposite sides of a parallelogram are parallel to each other.
Here, AB ∥ CD and AD ∥ BC
The opposite sides of a parallelogram are equal in length.
Here, AB = CD and AD = BC
The opposite angles of a parallelogram are equal in measure.
Here, Angle A = Angle C and
Angle B = Angle D.
Adjacent angles of a parallelogram add up to 180°
Here, Angle A + Angle B = 180°
Angle B + Angle C = 180°
Angle C + Angle D = 180°
Angle D + Angle A = 180°
Diagonals of a parallelogram bisect each other.
Here AC and BD bisect each other.
Types of a parallelogram
There are three special types of a parallelogram.
1. Rhombus: A parallelogram in which all sides are equal.
2. Rectangle: A parallelogram in which all angles are right angles and the diagonals are equal.
3. Square: A parallelogram with all equal sides and all angles equal to 90 degrees. The diagonals of a square are also equal.
Here all sides are equal and all the angles are right angles.
Diagonals AC and BD are equal.