Question

Find the are of the circle below.

Answer 1

To find the area of the circle with diameter = 18 cm

We will use the formula:

$\text{Area of a cirlce = }\pi r^2$

where r= radius of the circle

From the quesion diameter = 18 cm

radius = diameter/2

radius = 18cm/2 = 9 cm

substituting r = 9cm into the formula

$Area\text{ of a circle = }\pi(9)^2$$A\text{rea of the circle }=\text{ 81}\pi cm^2$

The above answer is when we are to leave the answer in terms of π

Otherwise if π is given to be 3.14 or 22/7 , we will simply substitute into the formula

That is given that π= 3.14

$\text{Area of the circle = 81 }\times3.14=254.34cm^2$