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Brown Math: Solving Polynomial Equations
The many facets of factoring polynomials and solving polynomial equations are explained here in great detail. Taking students from basic definitions through the Descartes Rule of Signs, this is a valuable tool for math classes.
Richland Community College
Real Zeros of Polynomial Functions
This site from the Richland Community College contains information on long and synthetic division, the remainder theorem and the factor theorem.
Help Algebra
Help algebra.com: Examples of Polynomial Equations
To solve polynomials of higher degree, use synthetic division as demonstrated here. The Rational Zero Theorem, Upper and Lower Bound Theorem, and Descartes Rule of Signs are explained.