Hendecagon Hendecagon In geometry, a hendecagon (also undecagon or endecagon) or 11-gon is an eleven-sided polygon. (The name "hendecagon", from Greek "hendeka" "eleven" and "gon–" "corner", is often preferred to the hybrid "undecagon", whose first part is formed from Latin "undecim" "eleven".) A "regular hendecagon" is represented by Schläfli symbol {11}. A regular hendecagon has internal angles of 147.27 degrees (=147 formula_1 degrees). The area of a regular hendecagon with side length "a" is given by As 11 is not a Fermat prime, the regular hendecagon is not constructible with compass and straightedge. Because 11 is not a Pierpont prime, construction
How many angels can dance on the head of a pin? dancing on a needle's point occurs in an expository work by the English divine, William Sclater (1575-1626). In "An exposition with notes vpon the first Epistle to the Thessalonians" (1619), Sclater claimed that scholastic philosophers occupied themselves with such pointless questions as whether angels "did occupie a place; and so, whether many might be in one place at one time; and how many might sit on a Needles point; and six hundred such like needlesse points." Harrison proposes that the reason an English writer first introduced the "needle’s point" into a critique of medieval angelology is that it makes for