The area of a circular pond is 21.5 m².

Work out the diameter of the circle.

Give your answer correct to the nearest centimetre.

You know the are of a circle is a=πr^2 so you substitute the a because it's given and you get 21.5 = πr^2 you divide by π getting 6.84=r^2 so you square root and you get 2.62. 2.62 is the radius so you multiply by 2 to get the diameter. The diameter of the circle is 5.24