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2 years ago

Find the area of a semi circle with a diameter of 28cm

Mathematics

1 answer:

Alexandra [31]2 years ago

8 0

since it has a diameter of 28, then its radius must be half that or 14.

$\textit{area of a circle}\\\\ A=\pi r^2~~ \begin{cases} r=radius\\[-0.5em] \hrulefill\\ r=14 \end{cases}\implies A=\pi (14)^2\implies A=196\pi ~\hfill \stackrel{\stackrel{semi-circle}{half~that}}{98\pi }$

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