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### The area of a circle is 16π cm squared. Find the diameter of the circle.

We can calculate the area of a circle using the following formula:

A = pi x r2

The area we are given is 16pi. Therefore, we can divide both sides by pi. So,

16pi = pi x r2

becomes

16 = r2

We can squareroot both sides to calculate the value of r.

sqrt16 = sqrt r2

Therefore r = 4

We can then use the formula d = 2r to calculate the diameter.

Therefore the diameter of the circle is 2x4 = 8cm.

10 months ago

Answered by Melissa, a 13 Plus Maths tutor with MyTutor

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