SOLUTION: Determine the area of an equilateral triangle inscribed in a circle of radius 12 cm.

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Question 255069: Determine the area of an equilateral triangle inscribed in a circle of radius 12 cm.
Answer by Greenfinch(383) About Me  (Show Source):
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Consider 1/3 of the equilateral triangle. It is a triangle with two sides of length 12 cm and the included angle of 120 degrees. Area is therefore
1/2 x 12 x 12 x sin 120 = 72 sin 120 = 72 x (sqrt 3)/2 = 36 sqrt 3.
So total is three times that or 108 sqrt 3 cm^2