Discovery Education
Discovery Education: Web Math: Algebra
This WebMath site provides links to tutorials and lessons in both Algebra I and II. Links to topics such as factoring, solving equations, polynomials, simplifying equations, graphing, and much more.
Purple Math
Purplemath: Numerical Approximation of Zeroes: The Midpoint Method
Explains the reasoning and methodology for the process of numerically approximating the zeroes of a non solvable polynomial.