what is an easy way to describe a golden triangle?

Answer 1

this page gives you a good start

http://mathworld.wolfram.com/GoldenTriangle.html

I also suggest you look into the Fibonacci numbers and the Golden Ratio
(1 + √5)/2

This will spark an interest in a very unique area of mathematics that will keep you occupied for a lifetime, like it has me.
My students used to try to get me off to that topic.