Sections:

Area and Length, Page 12

Sector: Example

Example: 

Find the area of a sector if the central angle measures 2pi/3 radians and the diameter of the circle is equal to 12 centimeters. Round your answer to the nearest tenth.

First find the radius:

r = d/2 = 12/2 = 6cm
Next, use the formula for the area of a sector:

A = 1/2 r^2 θ; A = 1/2 * (6)^2 * (2pi/3); A = 37.7 cm^2