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A circle has a sector with area 1/2 pi and central angle of 1/9 pi radians. What is the area of the circle

1 Answer

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Answer:


9\pi sq. units.

Explanation:

It is given that a circle has a sector with area
(1)/(2)\pi and central angle of
(1)/(9)\pi radians.

We know that, the area of sector is


A=(1)/(2)r^2\theta

where, r is radius and
\theta is central angle in radian.

Substitute the values of A and
\theta.


(1)/(2)\pi=(1)/(2)r^2((1)/(9)\pi)


1=r^2((1)/(9))


9=r^2


3=r

The radius of the circle is 3 units.

So, the area of circle is


A=\pi r^2


A=\pi (3)^2


A=9\pi

Therefore, the area of circle is
9\pi sq. units.

User Vedha Peri
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