Area of a circular sector

P=\dfrac{\alpha}{360^\circ}\cdot \pi r^2

Result unit: area units

What it describes

The area of a circular sector with central angle

\alpha

P

area of the sector

\alpha

central angle

[°]

r

radius

A sector is a "slice of pie" — the portion of the circle's area proportional to the central angle.

Areas of sectors, pie charts.

The radius is

r=6

and the central angle is

90^\circ

. Find the area of the sector.

Substitution

\alpha=90^\circ

r=6

Result

P=\dfrac{90}{360}\cdot\pi\cdot36=9\pi\approx28.3

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