Question

Find, correct to the nearest minute, the angle subtended at the centre of a circle of radius 5 cm by an of length 13 cm.

Answer 1

$\\ \tt{:}\dashrightarrow \ell=\dfrac{\Theta}{180}\pi r$

$\\ \tt{:}\dashrightarrow \Theta=\dfrac{180\ell}{\pi r}$

$\\ \tt{:}\dashrightarrow \Theta=\dfrac{180(13)}{5\pi}$

$\\ \tt{:}\dashrightarrow \Theta=149^{\circ}$

• 1°=60'

$\\ \tt{:}\dashrightarrow \Theta=149(60)$

$\\ \tt{:}\dashrightarrow \Theta=8940'$