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Suppose a sector of a circle with radius r has a central angle of θ. Since a sector is a fraction of a full circle, the ratio of a sector's area A to the circle's area is equal to the ratio of the BLANK to the measure of a full rotation of the circle. A full rotation of a circle is 2π radians. This proportion can be written as Aπr2=BLANK. Multiply both sides by πr2 and simplify to get BLANK, where θ is the measure of the central angle of the sector and r is the radius of the circle.

User Georgemp
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Answer:

Suppose a sector of a circle with radius r has a central angle of θ. Since a sector is a fraction of a full circle, the ratio of a sector's area A to the circle's area is equal to the ratio of the CENTRAL ANGLE to the measure of a full rotation of the circle. A full rotation of a circle is 2π radians. This proportion can be written as A/πr^2 =θ2π. Multiply both sides by πr2 and simplify to get A= θ/2 r^2 , where θ is the measure of the central angle of the sector and r is the radius of the circle.

Explanation:

i hope this helps a bit

User Hobo Joe
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Answer:

Central angle of θ


(A)/(\pi r^2) =(\theta)/(2\pi)


A=(\theta r^2)/(2), (\theta$ in radians)

Explanation:

Suppose a sector of a circle with radius r has a central angle of θ.

Since a sector is a fraction of a full circle, the ratio of a sector's area A to the circle's area is equal to the ratio of the central angle of θ to the measure of a full rotation of the circle.

A full rotation of a circle is 2π radians.

This proportion can be written as:
(A)/(\pi r^2) =(\theta)/(2\pi)

Multiply both sides by
\pi r^2


(A)/(\pi r^2) *\pi r^2=(\theta)/(2\pi)*\pi r^2

Simplify to get:


A=(\theta r^2)/(2)

Where θ is the measure of the central angle of the sector and r is the radius of the circle.

User Udalmik
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