Question

Define parallelogram along with their properties.

Answer 1

A parallelogram can be defined as a quadrilateral(which is a four sided polygon) with the following properties:
1) The opposite sides of a parallelogram are parallel and equal.
2) The opposite angles of a parallelogram are equal.
3) The diagonals of a parallelogram bisect each other.
For example,

The special cases of parallelogram are -
A rectangle is a parallelogram but with all four interior angles fixed at ${90}^{\circ }$
A rhombus is a parallelogram but with all four sides equal in length
A square is a parallelogram but with all sides equal in length and all interior angles ${90}^{\circ }$