Question

The radius of a semicircle is 1 inch. What is the semicircle's perimeter?

Answer 1

Check the picture below.

so let's find the arc's length and then add the 1 + 1 straight line for the perimeter.

`\textit{Circumference of a Semi-Circle}\\\\ C=\pi r ~~ \begin{cases} r=radius\\[-0.5em] \hrulefill\\ r=1 \end{cases}\implies C=\pi(1)\implies C=\pi \\\\[-0.35em] ~\dotfill\\\\ \stackrel{ \textit{\LARGE Lengths} }{\stackrel{arc}{\pi }~~ + ~~\stackrel{\textit{straight line}}{1+1}}\implies \pi +2\implies 3.14+2\implies \text{\LARGE 5.14}`