Instructional Video
Khan Academy

Khan Academy: Algebra: Completing the Square for Quadratic Equations

9th - 10th Standards
Demonstrates how to complete the square for the general form of a quadratic equation, ax^2 + bx + c = 0, which results in the quadratic formula. [9:31]
Instructional Video
Imagine Learning Classroom

Learn Zillion: Derive the Quadratic Formula: Completing the Square

9th - 10th Standards
In this lesson, you will learn how to derive the quadratic formula by completing the square. [6:01]