Question
How do I find the radius of a regular nonagon with an apothem of length 6.42in.
Answers
Steve
There are 9 40° angles in a circle, so the nonagon consists of 9 isosceles triangles, having angles of 40,70,70.
The radius is r, where
6.42/r = cos20°
The radius is r, where
6.42/r = cos20°