
Re: Trying to find perimeter of a regular pentagon
Posted:
May 30, 2013 1:46 AM


On Tuesday, May 28, 2013 8:15:05 AM UTC7, 130bcd wrote: > Hello, > > > > I have unsuccessfully tried to find the perimeter of a pentagon. The "radius" to the vertices is 130, which I tried to convert into 5 triangles but I can't find a formula for determining the length of the 3rd side of an isosceles triangle. > > > > The two equal length sides would, of course be 130 and the angle between them would be 72. > > > > Help, please!
Check out the explanatory article in
http://www.math.iastate.edu/thesisarchive/MSM/EekhoffMSMSS07.pdf
It derives all the formulas you need.

