A circle has a sector with area 1/2π and central angle of 1/9π radians . What is the area of the circle? Either enter an exact answer in terms of π or use 3.14 and enter your answer as a decimal.

Answer :

Answer:

[tex]9\pi[/tex]

Step-by-step explanation:

The area of a sector is given by;

[tex]A= \frac{1}{2} {r}^{2} \theta[/tex]

From the given information, the central angle is

[tex] \theta = \frac{ \pi}{9} [/tex]

and

[tex]A= \frac{\pi}{2} [/tex]

Let us substitute and solve for the radius, r.

[tex] \frac{ \pi}{2} = \frac{1}{2} \times {r}^{2} \times \frac{ \pi}{9} [/tex]

[tex]1 = \frac{ {r}^{2} }{9} [/tex]

[tex] {r}^{2} = 9[/tex]

[tex]r = \sqrt{9} = 3 \: units[/tex]

The area of a circle is given by:

[tex] = \pi \: {r}^{2} [/tex]

Substitute the radius to get:

[tex] = \pi \times {3}^{2} \\ = 9\pi[/tex]

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