Regular twentyth angle.
Twenty-corner or icosagoon is a figure with 20 angles and 20 sides. A regular twine angle is a regular polygon with n = 20; The angles of a regular twenty-angle are: α = ( n & # x2212; 2 ) n ⋅ 180 & # x2218; = 18 20 ⋅ 180 & # x2218; = 162 & # x2218; {\displaystyle \alpha ={\frac {(n-2)}{n}}\cdot 180^{\circ }={\frac {18}{20}}\cdot 180^{\circ }=162^{\circ }}
The area A for a regular twint angle is given by the following formula (with a the length of one side): A = 5 a 2 cot π 20 {\displaystyle A=5a^{2}\cot {\frac {\pi }{20}}} & # x2248; 31 , 5688 a 2 {\displaystyle \approx 31,5688a^{2}\,} Also see
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