 The word ‘quad’ states as four. Quadrilaterals are a two-dimensional plane figure, which has four edges and four vertices. The sides of the quadrilaterals are straight lines and joint with each other end to end. It is nothing but a polygon which has four corners and four sides. These quadrilaterals can be seen in different shapes, regular or irregular. The examples are a kite, a deck of cards, etc. We will learn the types of quadrilaterals here.

• It has four sides, four corners/vertices and four angles
• It has both regular and irregular shape
• Total of all its interior angles is equal to 360 degrees

There are various types of quadrilaterals, such as:

1. Trapezium: One of the opposite sides are parallel
2. Parallelogram: Both the opposite sides are parallel and equal in length.
3. Squares: All the sides are equal and the angles are at 90 degrees.
4. Rectangle: Opposite sides are equal and angles are at 90 degrees.
5. Rhombus: All the sides are equal and diagonals bisect at 90 degrees.
6. Kite: Two pairs of adjacent/neighbouring sides are of equal length. Area of Quadrilateral: The region occupied by any type of the quadrilateral in a two-dimensional plane is its area. The formulas for different types of quadrilaterals are given by:

 Area of a Parallelogram Base x Height Area of a Rectangle Length x Width Area of a Square Side x Side Area of a Rhombus 1/2 x Diagonal 1 x Diagonal 2 OR Base x Height Area of a Kite 1/2 x Diagonal 1 x Diagonal 2

Q.1: Find the area of the rectangle whose length is 4cm and width is 3.5cm.

Solution: Given, Length of the rectangle = 4cm

And width of the rectangle = 3.5cm

Since, area of the rectangle, A = Length x Width

A = 4cm x 3.5 cm

A = 14cm2

Q.2 If the area of the square is 121cm2, then find the length of its sides.

Solution: Given, Area of the square = 121cm2

We know,

Area of the square = side2

Therefore,

121 = side2

Or Side = √121 = 11

Hence, the side of the square is 11cm.