PERIMETER 1

Find perimeter of a regular polygon with 5 sides inscribed in a circle of radius 6cm.

Solution

P = 2nrSin(180⁰/n)

n= 5  and r=6cm

P = 2 x 5 x 6 x Sin(180⁰/5)

P = 60 x Sin36⁰

P = 60 x 0.5878

Hence P = 35.268cm

TRY THIS…………….. 

Find perimeter of a regular polygon with 9 sides inscribed in a circle of radius 7cm.