Year 9 Interactive Maths - Second Edition

Area of a Circle

A circle with radius r units has an area of A square units given by the formula

where 

Example 17

Find the area of a circle whose diameter is 28 m.

Solution:

Example 18

Find the area of a circle whose diameter is 19 cm.

Solution:

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 ]