Geometry question - what is the area of a regular decagon inscribed in a circle with an apothem of 1 foot? Thanks!!?
回答 (1)
2016-04-05 11:53 pm
s = length of one side = 2tan(18°)
perimeter = 10s = 20tan(18°) ≅ 6.5 ft
area = ½·apothem·perimeter = ½·1·6.5 = 3.25 ft²
perimeter = 10s = 20tan(18°) ≅ 6.5 ft
area = ½·apothem·perimeter = ½·1·6.5 = 3.25 ft²
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