Question

what is the area of the circle in terms of pi

Answer 1

Area of circle = Pie x (radius)^2

Answer 2

In this hub I will show you how to find the area of circle giving your answer in terms of Pi (π).

First of all you need to remember the formula for calculating the area of a circle:

A = πr²

A stands for area, π stands for Pi and r is the radius of the circle (the distance halfway across).

Example 1

Work out the area of circle that has a radius of 7m, giving your answer in terms of Pi.

All you need to do is substitute r = 7 into A = πr²

A = πr²

= π × 7²

Since 7² = 49 (since 7 × 7 = 49) then you have:

= π × 49.

= 49π

So the final answer is 49π m² (put the number before Pi)

Example 2

Work out the area of circle that has a diameter of 22cm, giving your answer in terms of Pi.

This time the diameter is given (the distance all the way across) so you need to halve this to give the radius. Therefore, plug in r = 11 into A = πr²

A = πr²

= π × 11²

Since 11² = 121 (since 11 × 11 = 121) then you have:

= π × 121.

= 121π

So the final answer is 121π cm² (put the number before Pi)

Example 3

Work out the area of this circular lawn giving your answer in terms of Pi.