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1 vote
The area of a circle is 78.5 square meters. what is the radius ?

2 Answers

5 votes

\bf \textit{area of a circle}\\\\ A=\pi r^2\quad \begin{cases} r=radius\\ ------\\\ A=78.5 \end{cases}\implies 78.5=\pi r^2\implies \cfrac{78.5}{\pi }=r^2 \\\\\\ \sqrt{\cfrac{78.5}{\pi }}=r
User Adam Holmberg
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4 votes
The radius will be = 5
User Jeanny
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