Pearson Geometry Common Core, 2011
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Pearson Geometry Common Core, 2011 View details
8. Geometric Probability
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Exercise 52 Page 674

A sector of a circle is the region bounded by an arc of the circle and the two radii to the arc's endpoints. The area of a sector of a circle is the product of the area of the circle and the measure of the arc divided by 360.

12πcm^2

Practice makes perfect

A sector of a circle is the region bounded by an arc of the circle and the two radii to the arc's endpoints.

The area of a sector of a circle is the product of the area of the circle and the measure of the arc divided by 360.

Area of sectorAOB: m AB/360* π r^2

Recall that the measure of a minor arc is equal to the measure of its corresponding central angle. We are told that the central angle measures 30^(∘). Therefore, the measure of its corresponding arc is also 30^(∘).

We want to find the area of sector AOB in ⊙ O. We are given that the radius of the circle is 12 centimeters and we know that the measure of its corresponding arc is 30^(∘). Therefore, we have all the information we need to use the formula to find the area of sector AOB.
A= mAB/360* π r^2
A=30/360* π ( 12^2)
Evaluate right-hand side
A=30/360* π (144)
A=30/360* 144π
A=4320/360π
A=12π
We found that the area of the sector is 12π square centimeters.