How to find area

Students can learn How to Find Area of a Shape. They can learn to solve problems assocaited to it. Geometry deals with the study of 2 dimensional shapes and 3 dimensional solids and their properties like area, volume, length, surface area etc,.

The amount of surface occupied by the plane figure is called its Area.  The SI unit of area is square meter (m2). Area of regular or irregular shape can be obtained by using basic formulas defined for basic structures like square, triangle, rectangle, circle etc.

Here are some formulas which aid students to learn how to find the area of a shape.

Area of Square = a^2     

Area of Rectangle = ab       

Area of Parallelogram = bh         

Area of Trapezoid = h/2 (b1 + b2)   

Area of Circle = `pi`r 2          

Area of Triangle  = `(1)/(2) b.h`     

In the following example students can learn how to find area of a shape. Students can follow similar steps to compute the area of various shapes.

Let us take l=10 meters and b=6 meters

For ex:  This example shows how to find the area of a shape. This is the compuation of the area of a Rectangle. The area of a rectangle is the product of its length and width. The formula to be used is A = l * w, where l = length and w = width of the rectangle



Substituting the values of the dimensions in the formula and necessary computation is to be done to obtain the final value. For rectangle, it can be calculate as follows:

A= l * b = 10 * 6 = 60

The area of the rectangle is 60 square meters


Finding area


Here are some problems on how to find area of a shape.

Let us consider another sample problems on how to find area of a shape to have a better understanding.

For example, how to find area of a shape, the shape being a Circle in this example.



The area of the circle is A= π * r 2                  , where r is the radius of the circle.

Here, the value of the constant is π=3.14

Ex:  How to find area of a circle with radius 4 m.

Sol:  Radius = 4 m.

substituting the values in the formula  A = Π r2

A = 3.14 *42

= 50.24

The area of the circle is calculated to be 50.24 square meters.

Pro 1:   How to Find area of a circle whose radius is 5meters.

Ans: 78.5 square meters

Pro 2:  How to Find area of a rectangle whose dimesions are 3meters and 9meters.

Ans: 27square meters

Pro3 :  The side of a cube is 5meters.Find its total surface area.

Ans:150 square meters

Pro 4: The radius of a sphere is 4cm.Find its area.

Ans: 200.96 square centimeters

Find area of irregular shape


First the irregular figure is to be split into known regular figures. We already know how to find the area of a shape i.e. regular shapes. Thus, the area of the irregular figure can be calculated. Students can learn about how to find area of a shape which is irregular from the following examples:

Ex: Find the area of the following irregular figure



Sol: To find its area it is to be divided into known figures. The above given irregular figure can be divided into two known figures. That can be done a shown in the above figure.

Step 1: In the figure, the dotted line splits the irregular figure into two known figures like the rectangle with length (L) 14mm and width (W) 10mm and semi- circle with diameter (D) 14mm. Now the area of the irregular figure can be calculated as follows:

Step 2; Area of irregular figure= (Area of rectangle) + (Area of semi-circle)

= (L*W) + (π * D *D*0.25)

Step 2:                                        = (14 *10) + (3.14 *14*14*0.25)

Step 3:                                        = 140 + 153.86

Step 4:                                         =293.86 square mm

Thus the area of an irregular figure can be calculated.


Problems on Irregular figures:

Find the Area of the following irregular figures


Answers:      1. 51 square cm

2. 60 square cm

3. 27 square inches

Students can learn how to find area of a shape from the above examples and practice more problems on similar lines.