Question

The circle below has center 0, and its radius is 4 mm. Given that m ZAOB = 50°, find the length of the major arc ACB.

Answer 1

$\textit{arc's length}\\\\ s=\cfrac{r\theta \pi }{180}~~ \begin{cases} r=radius\\ \theta =\stackrel{in~degrees}{angle}\\[-0.5em] \hrulefill\\ r=4\\ \theta =50 \end{cases}\implies s=\cfrac{(4)(50)\pi }{180}\implies s=\cfrac{10\pi }{9}~mm$