Purple Math
Purplemath: Completing the Square: Deriving the Quadratic Formula
View examples on completing the square and deriving the quadratic formula. The key to solving by completing the square is "practice, practice, practice". By so doing, the process will become more "automatic", and you'll be much more...
Math Is Fun
Math Is Fun: Derivation of Quadratic Formula
The learning resource investigates the quadratic formula. Students learn how the formula is derived by completing the square and solving for x.
CK-12 Foundation
Ck 12: Algebra: The Quadratic Formula: Deriving and Using the Quadratic Formula
[Free Registration/Login may be required to access all resource tools.] This lesson covers deriving the quadratic formula and using it to solve any quadratic equation.
Math Medics
S.o.s. Math: Quadratic Equations Quadratic Formula
Here you can find a general overview of the quadratic formula, complete with a full breakdown of how to come up with the quadratic formula with a quadratic equation, as well as am example of using the quadratic formula to solve a...
Math Medics
S.o.s. Math: Quadratic Formula: Completing the Square
This tutorial explains the quadratic formula by reviewing its origin from the process of completing the square. Includes examples and a few exercises.
CK-12 Foundation
Ck 12: Algebra: Quadratic Formula
[Free Registration/Login may be required to access all resource tools.] This lesson covers deriving the quadratic formula and using it to solve any quadratic equation.
Paul Dawkins
Paul's Online Notes: Algebra: Quadratic Equations Part Ii
Detailed math tutorial features notes and examples that illustrate how to solve quadratic equations using complete the square then use that to derive the quadratic formula.
Wolfram Research
Wolfram Math World: Quadratic Equation
This MathWorld site shows how to derive the quadratic formula.
Illustrative Mathematics
Illustrative Mathematics: F Bf, a Sse Building a General Quadratic Function
This task is a followup to the one called 'Building an explicit quadratic function.' In this one, students follow the same process with a general quadratic function. The operations take place in the opposite order and the goal is to find...
Help Algebra
Help algebra.com: Quadratic Formula
This presentation of the quadratic equation includes a discussion on the discriminant and a derivation of the quadratic formula.
Purple Math
Purplemath: Completing the Square: Deriving the Vertex Formula
This resource describes in steps how to derive the vertex formula.
Lawrence Hall of Science
The Math Page: Topics in Pre Calculus: Completing the Square
Here is a site that clearly and thoroughly explains how to solve quadratic equations by completing the square. The quadratic formula is derived using this method on this page. Point this site out to students who have been absent or who...
Other
Center for Technology and Teacher Education: Parabola Lesson Plan
This site is a lesson plan on construction of a parabola using the definition. Geometer's Sketch Pad software is beneficial for the lesson. Through the lesson learners develop gemetric constructions of parabolas, use the distance formula...