**Title:** Now, where did THAT come from? Deriving the Quadratic Formula

**Description:**
Generally, teachers expect students to memorize the quadratic formula and to know that you use it after exhausting all other means of solving a quadratic equation, i.e. as a last resort. This technology-based lesson is designed to assist students with deriving the formula on their own. Students must first be familiar with complex numbers and the process of “completing the square.”
This lesson plan was created by exemplary Alabama Math Teachers through the AMSTI project.

**Standard(s): **

[MA2013] AL1 (9-12) 18: Solve quadratic equations in one variable. [A-REI4]

[MA2013] AL1 (9-12) 18: Solve quadratic equations in one variable. [A-REI4]

[MA2013] AL1 (9-12) 21: Solve a simple system consisting of a linear equation and a quadratic equation in two variables algebraically and graphically. [A-REI7]

[MA2013] AL2 (9-12) 4: Solve quadratic equations with real coefficients that have complex solutions. [N-CN7]

[MA2013] ALC (9-12) 6: Use the extreme value of a given quadratic function to solve applied problems. (Alabama)