Question

Find the area of this semi-circle with diameter, d = 20cm. Give your answer as an expression in terms of π

Please make sure it's in terms of π !
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Answer 1

Answer:

$50\pi {cm}^{2}$

Step-by-step explanation:

Area of a circle is

$a = \pi \times {r}^{2}$

Diameter = 20cm therefore the Radius = 10cm.

First we must find the area of the whole circle. All we need to do is plug in.

$a = \pi \times {r}^{2} \\ a = \pi \times {(10)}^{2} \\ a = \pi \times 100 \\ a = 100\pi$

The area of the WHOLE circle is 100pi

A semi circle is HALF a circle, so what is the area of the semi-circle?

All you must do is divide the Whole circle into two

$100\pi \div 2 \\ 50\pi$

Make sure to add back our units.

$50\pi {cm}^{2}$

Brainliest Appreciated