This article reviews a few different methods that Fibonacci could have used to find a real solution to the polynomial

[x^3 + 2x^2 + 10x = 20]

I will explain what the two most prominent methods are.

You can access the article via this link:

http://www.jstor.org/stable/25653745

Fibonacci’s Forgotten Number Revisited

Richard Maruszewski

The College Mathematics Journal , Vol. 40, No. 4 (September 2009), pp. 248-251

Published by: Mathematical Association of America

Article Stable URL: http://www.jstor.org/stable/25653745