The central angle of a sector is 72° and the sector has an area of #5pi#. How do you find the radius?

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Answer 1 · 2017-10-09T19:08:18

#5#

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Area of a sector is:

#1/2r^2theta#

#theta# measured in radians.

#72^o = (2pi)/5#

So:

#1/2r^2((2pi)/5)= 5pi#

#r^2= (10pi)/((2pi)/5)=25=> r=sqrt(25)=5#