Question

Circle S is shown. Line segment R T is a diameter. The length of S T is 4. Sector R S T is shaded. The measure of central angle RST is radians. What is the area of the shaded sector? 4Pi units squared 8Pi units squared 16Pi units squared 20Pi units squared

Answer 1

Answer: 8π (Option B)

Step-by-step explanation:

Answer 2

Answer:

Second option is correct.

8\pi units^{2}

Step-by-step explanation:

The shaded sector is half the area, because its divided in two parts by the diameter, which is in the middle. So, one way we could get the answer is finding the total area, then divide it by two, like this:

$A=\pi r^{2} \\A=\pi (4)^{2} \\A=16\pi$

Then, the shaded sector is half:

$A_{shaded}=\frac{A}{2}=\frac{16\pi}{2}=8\pi units^{2}$

Therefore, the correct answer is the second option.