Geometry
posted by mary on .
Problem : Howm do you find the area of a circle circumscribed about a regular pentagon with a perimeter of 50 inches.
So far I each side of pentagon is 10. How do I find the radius of the circle? Is this the correct direction to go?

Ahh the golden ratio, and now you will know why followers of Pythagoras used the pentagon as a secret symbol: it harbors secret numbers.
http://www.treenshop.com/Treenshop/ArticlesPages/FiguresOfInterest_Article/The%20Regular%20Pentagon.htm