Area is the size of the region enclosed
within a plane figure. To the carpenter or carpet layer, who is concerned
with the amount of material to be used, measurement of area is very
important.

Area is measured in square units. The most frequently used units of area are mm^{2}, cm^{2} and m^{2}. Land areas are often given in hectares (ha).

1 ha = 10 000 m^{2}

The area of plane figures are often required to solve real world
problems.

Area of a Square

A square with sides of length s units
has an area of A square units given by the formula

Example 6

Find the area of a square flower-bed of side 4.5 m.

Solution:

So, the area is 20.25 m^{2}.

Note:

To find the area of a region enclosed within a plane figure, draw a
diagram and write an appropriate formula. Then substitute the given values
and use a calculator, if necessary, to obtain the required area.

Area of a Rectangle

A rectangle with length l units and
width w units has an area of A square units given by the formula

Example 7

Find the area of a rectangular field 40 m long and 30 m wide.

Solution:

Area of a Triangle

A triangle with base b units and height h units has an area of A square units given by the formula

Example 8

Find the area of a triangle with base 14 cm and height 10 cm.