In a circle, a 90 sector has area 64π ft2. What is the radius of the circle?

 

In a circle, a 90° sector has area 64π ft2. What is the radius of the circle?     

 

                Entire circle  =  (4)(64 π)  =  256 π     

 

                                         A  =  π r²  =  256 π        

divide both sides by π                  r²  =  256     

                                                     r    =  16     

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