Area of a regular n-gon is ns^2/(4tan(pi/n))

Created by KnaveOfAllTrades on 2015-05-03; known on 2015-05-03; judged right by KnaveOfAllTrades on 2015-05-03.

• KnaveOfAllTrades estimated 46% on 2015-05-03
• KnaveOfAllTrades   judged this prediction right on 2015-05-03.