A circle has a sector with area (3/2) pi and central angle of 60°.
What is the area of the circle?
Either enter an exact answer in terms of it or use 3.14 for it and enter your answer as a decimal.

A circle has a sector with area (3/2) pi and central angle of 60°. What is the area of the circle? Either enter an exact answer in terms of it or use 3.14 for i class=

Answer :

jacob193

Answer:

[tex]9\pi[/tex], which is approximately [tex]28.26[/tex].

Step-by-step explanation:

Consider two sectors in the same circle. The area of the two sectors is proportional to their central angles. In other words, if the central angle is [tex]\theta_1[/tex] for the first sector in this circle, and [tex]\theta_2[/tex] for the second, then:

[tex]\displaystyle \frac{\text{Area of Sector 1}}{\text{Area of Sector 2}} = \frac{\theta_1}{\theta_2}[/tex].

In this question, think about the whole circle as a sector. The central angle of this "sector" would be [tex]360^\circ[/tex] (a full circle.) Compare the area of this circle to that of the [tex]60^\circ[/tex]-sector in this circle:

[tex]\displaystyle \frac{\text{Area of Circle}}{\text{Area of $60^\circ$-Sector}} = \frac{360^\circ}{60^\circ} = 6[/tex].

In other words, the area of this circle is six times that of the [tex]60^\circ[/tex]-sector in it.

The area of that [tex]60^\circ[/tex]-sector is [tex]\displaystyle \frac{3}{2}\pi[/tex]. Therefore, the area of this full circle will be [tex]\displaystyle 6 \times \frac{3}{2}\pi = 9\pi \approx 28.26[/tex].

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