Area of a sector of a circle, whose angle is (7pi)/6 is 175pi/12. What is its radius?

1 Answer
Oct 7, 2016

Radius of circle is 5 feet

Explanation:

If the sector has an angle theta and radius r,

its area is 1/2r^2theta

As such we have 1/2r^2theta=175pi/12, where r is in feet.

or 1/2r^2xx(7pi)/6=175pi/12

or r^2=175pi/12xx(2xx6)/(7pi)

= r^2=175cancelpi/cancel12xxcancel(2xx6)/(7cancelpi)

= 175/7=(5xx5xx7)/7=5xx5

Hence radius of circle is 5 feet