Year 9 Interactive Maths - Second Edition

Area

Area is measured in square units.  The most frequently used units of area are mm², cm² and m².  Land areas are often given in hectares (ha).

1 ha = 10 000 m²

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

Area of a Square

Example 6

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

Solution:

So, the area is 20.25 m².

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

Example 7

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

Solution:

Area of a Triangle

Example 8

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

Solution:

Key Terms

area, square units, hectares

Study Another Topic in Chapter 14: Measurement

[ Perimeter ] [ Circumference of a Circle ] [ Area ] [ Problem Solving ] [ Area of Other Figures ] [ Area of a Trapezium ] [ Area of a Rhombus ] [ Area of a Kite ] [ Area of a Circle ] [ Area of a Annulus ] [ Composite Figures ] [ Surface Areas ] [ Total Surface Area of a Cuboid ] [ Curved Surface Area of a Cylinder ] [ Total Surface Area of a Cylinder ] [ Volume ] [ Volume of a Cuboid ] [ Volume of a Cylinder ] [ Volume of a Triangular Prism ] [ Capacity ] [ Problem Solving ] [ Problem Solving Unit ] [ Symbols ] [ Index ]