What is the exact area of a circle with a diameter of 20 cm? 400cm^2 10cm^2

What is the exact area of a circle with a diameter of 20 cm? 400πcm^2 10πcm^2 100πcm^2 20πcm^2

2 months ago

Solution 1

Guest Guest #1798
2 months ago
Hi there! The answer is 100πcm^2

The radius of a circle can be found by dividing the diameter by 2. In other words : the radius is half of the diameter.
Therefore, the radius of a circle with a diameter of 20 cm is 10 cm.

The exact area of a circle can be found using the following formula:
a = \pi \times \: {r}^{2} \\ with \\ a = area \\ r = radius

In order to find our answer, we need to plug in the data from the question.
a = \pi \: \times {10}^{2} = 100\pi

Hence, the answer is 100πcm^2.

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Hope this Helped :D
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I got a 100% for this answer :)

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