Question

A sector with a radius of 8 cm has an area of 56pi cm2. What is the central angle measure of the sector in radians?

Answer 1

Answer:

$\frac{7\pi}{4}$.

Step-by-step explanation:

Given information:

Radius of circle = 8 cm

Area of sector = $56\pi\text{ cm}^2$

Formula for area of sector is

$A=\dfrac{1}{2}\theta r^2$

where, r is radius and $\theta$ is central angle in radian.

Substitute $A=56\pi$ and r=8 in the above formula.

$56\pi=\dfrac{1}{2}\theta (8)^2$

$56\pi=\dfrac{64}{2}\theta$

$56\pi=32\theta$

$\dfrac{56\pi}{32}=\theta$

$\dfrac{7\pi}{4}=\theta$

Therefore, the measure of the sector in radians is $\frac{7\pi}{4}$.