Question

In figure 7.34, if A(P-ABC) = 154 cm2 radius of the circle is 14 cm,Find
(1) ∠APC.
(2) L(arcABC) .

Answer 1

Area of sector PABC , A = 154 cm^2
Radius of sector, r = 14 cm
Take
$\pi = \frac{ 22 }{7}$

1) Area of sector, =
$\frac{\pi {r}^{2} }{360 \degree} \times \theta \\ = > \frac{\pi \times {14}^{2} }{360 \degree} \times \theta = 154 {cm}^{2} \\ = > \theta = 90 \degree$

2) Length of Arc
$= \frac{\pi \times r \times \theta}{180 \degree} = \frac{\pi \times 14 \times 90 \degree}{180 \degree} = 22cm$