## Quadrilateral definition

A closed figure bounded by **four line segments**, that do **not intersect each other** except at the endpoints is called a quadrilateral.

The quadrilateral is derived from two words, ‘quadri‘ which means four, and ‘lateral‘ which means side.

### Quadrilateral examples in real life

We can see the **shape of quadrilaterals** in several objects around us, like in a deck of cards, a chessboard, a kite, a tub of popcorn, and an arrow.

### Properties of a Quadrilateral

- A quadrilateral has 4 sides and 4 vertices.
- A quadrilateral has 4 angles and two diagonals.
- The sum of the angles of a quadrilateral is always 360°.

## Types of Quadrilaterals

Quadrilaterals can be categorized into

- Parallelogram
- Rectangle
- Rhombus
- Square
- Trapezium
- Kite

### 1. Parallelogram

A quadrilateral is a parallelogram if

- its opposite sides are equal.
- opposite angles are equal.
- its diagonals bisect each other.
- it has one pair of opposite sides parallel and equal.

### 2. Rectangle

A rectangle properties are:

- opposite sides are equal.
- each angle is a right angle.
- diagonals are equal.
- diagonals bisect each other.

### 3. Rhombus

A rhombus properties are:

- all sides are equal.
- opposite angles are equal.
- diagonals bisect each other at a right angle.

### 4. Square

A square properties are:

- all the sides are equal.
- each angle is a right angle.
- diagonals are equal.
- diagonals bisect each other at a right angle.

### 5. Trapezium

A trapezium properties are:

- one pair of opposite sides is parallel.
- interior angles on the same side of each of the non-parallel sides are supplementary.

### 6. Kite

- two pairs of adjacent sides are equal and opposite sides are unequal.
- diagonals intersect each other at right angles.
- the diagonals bisects the other diagonal.
- only one pair of opposite angles is equal.