#3**+10 **

Sorry, rosala...I should have explained more....Phi is the irrational number (1 + √5) / 2 ≈ 1.61803398874989485

If you have regular pentagon of side length = 1, then the length of one of its diagonals turns out to be "Phi"

Also....if you're familiar with the Fibonacci Series.......as the series grows larger, the ratio between a successive term and its preceding term tends towards Phi....!!

Athough you probably have enough studying to do in school....here's a whole website devoted to Phi....http://www.maths.surrey.ac.uk/hosted-sites/R.Knott/Fibonacci/phi.html

(You may find it interesting to just look at a little of it at a time...!!!)

CPhill
Dec 30, 2014

Dec 29, 2014