Regular and Irregular Figures

A figure bounded by line segments is a regular figure.

Figures bounded by curved lines are called irregular figures.

$Regular and Irregular Figures$

The space enclosed by the line segments is called the area of a figure.

For example:

Given below is a square bounded by four line segments each of length 1 cm.

$Square of Sides 1 cm$

The area of the square of sides 1 cm is 1 square cm (sq. cm) or centimetre² (cm²)

What is the area of a square of sides 3 cm?

$Square of Sides 3 cm$

The above square consists of 9 small squares of area 1 sq. cm each.

Therefore, the area of square ABCD is 9 sq.cm (cm²)

Note: Square cm or centimetre² is the unit of area.

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