CK-12 Foundation
Ck 12: Factor Quadratics: Methods for Solving Quadratic Functions
[Free Registration/Login may be required to access all resource tools.] A review of the three major methods of solving quadratic functions for "x" intercepts.
Purple Math
Purplemath: Completing the Square: Solving Quadratic Equations
Purplemath gives several examples which clearly show the process of completing the square to find the maximum and minimum solutions to a quadratic equation.
BBC
Bbc: Higher Bitesize Maths: Quadratic Theory
A tutorial on quadratics presents topics including: factoring and solving quadratics, graphing quadratic functions, using completing the square and the quadratic formula to solve functions, the discriminant and conjugates. Plenty of...
Khan Academy
Khan Academy: Equations & Inequalities Word Problems
HSA-CED.A.1: Interactive resource which create equations and inequalities in one variable and use them to solve problems. Include equations arising from linear and quadratic functions, and simple rational and exponential functions....
Illustrative Mathematics
Illustrative Mathematics: A Rei Two Squares Are Equal
This task asks students to solve a quadratic equation in as many different ways as they can. Aligns with A-REI.B.4 and A-REI.D.11.
Khan Academy
Khan Academy: Lsn 13: Systems of Equations, Algebraic and Graphical Representations
Lesson 3 of 4 for Passport to Advanced Math. Students will solve systems of equations in two variables in which one equation is linear and the other equation is quadratic or another nonlinear equation; relate properties of the function f...