# Area of Sectors

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Videos, worksheets, games and activities to help Geometry students learn how to find the area of sectors.
What is a sector?

A sector is part of a circle bound by the central angle and its intercepted arc. You can think of it as the area of a "slice of pizza".

What is the formula for the area of sector?

$$\begin{array}{l}\frac{{{\rm{central \: angle}}}}{{360^\circ }} = \frac{{{\rm{sector}}}}{{\pi {r^2}}}\\{\rm{sector}} = \frac{{{\rm{central \: angle}}}}{{360^\circ }} \times \pi {r^2}\end{array}$$

Area of a Sector
A sector in a circle is the region bound by two radii and the circle. Since it is a fractional part of the circle, the area of any sector is found by multiplying the area of the circle, π×r2, by the fraction x/360, where x is the measure of the central angle formed by the two radii.
This video shows two examples, one for finding the sector of a circle and the other to find the radius of a circle with a given sector area.

Finding the area of a sector of a circle
This video explains how to find the area of a sector.

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