Question

Find the area of the shaded region. Write your answers in terms of pi.

Answer 1

Answer:

Area of shaded region is $\pi$

Step-by-step explanation:

A = $r^{2}$θ /2

Firstly, calculate the area of sector of radius  8cm.

A =8$\pi$

Secondly, calculate the area of sector of radius  12cm.

A = 9$\pi$

Calculate the difference = 9$\pi$-8$\pi$ = $\pi$

Answer 2

Answer:

10 (cm.²)

Step-by-step explanation:

1. the area of the circle with r=12 is: πr²=144π (cm²);

2. the area of the circle with r=8 is: 64 (cm²);

3. the area of the region between the radius 8 and 12 cm is: 144-64=80 (cm²);

4. the measure for the circle is 360°, then the area of the shaded region for 45° is: 45/360=A/80; ⇒ 10 (cm²).