The sector of a circle has perimeter of 144 cm and central angle 180o. Find its radius?
Choose the correct choice from the following answers.
A) 25 cm  B) 32 cm  C) 14 cm  D) 28 cm  E) 21 cm
Let the radius is x cm   Perimeter of the sector = length of the arc + 2(radius)   144= (180/360 * 2 * 22/7 * x) + 2(x)   144= 22x/7 + 2x   144= 36x/7   36x= 1008   x = 28   Answer: 28 cm
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The sector of a circle has perimeter of 144 cm and central angle 180o. Find its radius?