A quadrilateral is special types of polygon which has four sides. Any quadrilateral has four sides ,four angles, four vertex. There are five types of regular polygon (quadrilateral). Trapezium, Parallelogram, Rhombus. Rectangle and Square. There is also a quadrilateral which has no regular shape that is known as only quadrilateral.

## Trapezium

**TRAPEZIUM: **A quadrilateral which has exactly one pair of opposite sides** **as** parallel** is called trapezium. The following figures are of trapezium** **because in each figure one pair of opposite sides are parallel**.**

## Parallelogram

**PARALLOGRAM: **A quadrilateral is a parallelogram if opposite sides are parallel. The following figure shows a parallelogram.

In the above figure, quadrilateral is a parallelogram because AB?DC, AD?BC.

**PROPERTIES OF A PARALELLOGRAM**:

- Opposite sides are equal. So AB =DC, AD = BC.
- Opposite angles are equal. So
*L*A=*L*C and*L*B=*L*D - Sum of adjacent angles are equal to 180
^{o}. - Diagonals are not equal in length. So AC
**$\ne$**BD.

## Rhombus

**RHOMBUS: **A parallelogram having all sides are equal, called a rhombus. The following figure shows a rhombus.we use this in finidng area of

In the above figure, quadrilateral is a rhombus because AB = BC =CD = DA and. AB?DC, AD?BC.

**Properties of A Rhombus**:

- All sides are equal. So. AB = BC =CD = DA
- Opposite angles are equal. So
*L*A=*L*C and*L*B=*L*D - Sum of adjacent angles are equal to 180
^{o}. - Diagonals are not equal in length. So AC
**$\ne$**BD.. But intersect each other at right angle. So*L*AOD = Right Angle.

## Rectangle

**RECTANGLE: **A parallelogram having one angle equal to 90^{o}, is called a rectangle.The following figure shows a rectangle.

In the above figure, quadrilateral is a rectangle because, AB =DC, AD = BC and. AB?DC, AD?BC.

**PROPERTIES OF A RECTANGLE**:

- Opposite sides are equal. So. AB =DC, AD = BC.
- All angles are equal and of 90
^{o}. - Sum of adjacent angles are equal to 180
^{o}. - Diagonals are equal in length. So AC = BD.

## Square

**SQUARE: **A rhombus having one angle equal to 90^{o}, called a square. The following figure shows a square.

In the above figure, quadrilateral is a square because AB = BC =CD = DA and. *L*AOD = 90 degree and *L*ADC = 90 degree.

**PROPERTIES OF A SQUARE**:

- All sides are equal. So. AB = BC =CD = DA
- All angles are equal.
- Sum of adjacent angles are equal to 180
^{o}. - Diagonals are equal in length. So AC= BD. and intersect each other at right angle. So
*L*AOD = 90 degree

## Kite

**KITE: **A quadrilateral is a kite if its one both pairs of adjacent sides are unequal. The following figure shows a kite.

In the above figure, quadrilateral is a kite because AB **$\ne$ **BC and AD **$\ne$ **DC.

**PROPERTIES OF A KITE**:

- Two pair of adjacent sides are equal. So AD =AB, DC = BC.