How to calculate the area within a shape

Contents

What is Area

Area is a measure of enclosed surface of any shape. It tells us how much space is covered. Calculating the area of a surface is a useful skill. It can help you determine how much tiles you need to lay in a room, how much paint you need for a wall, how much seeds you need to plant in your garden, etc.

Observe the spaces in the shape below. The shaded part represent 1 cm x 1 cm = 1 cm² This is the area of that shaded space or the number of square units needed to cover a region.

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Therefore area of a shape 6 cm long (base) and 3 cm wide (height) is 18 cm².

Area of rectangle = b x h

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Example:

Find the area of a square with sides 3 cm.

The area = s x s = 3 cm x 3 cm = 9 cm²

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As you have seen you can measure area using the grid method. Once you know the size of one grid you can calculate the area of the surface.

EXERCISES ON A GEOBOARD.

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Use the geoboards for understanding area. Find the area of a number of shapes you make on your geoboard.

e-geoboard

How to make your own geoboard

Worksheets

Click here for more worksheets.