# Completing the square and the quadratic formula

7 videos
6 skills
You're already familiar with factoring quadratics, but have begun to realize that it only is useful in certain cases. Well, this tutorial will introduce you to something far more powerful and general. Even better, it is the bridge to understanding and proving the famous quadratic formula. Welcome to the world of completing the square!

### Solving quadratic equations by square roots

VIDEO 11:03 minutes
Solving Quadratic Equations by Square Roots

### Solving quadratics by taking the square root

PRACTICE PROBLEMS
Solve quadratics by taking the square root.

### Solving quadratic equations by completing the square

VIDEO 14:06 minutes
Solving Quadratic Equations by Completing the Square

### Solving quadratics by completing the square 1

PRACTICE PROBLEMS
Find the roots of a quadratic equation by completing the square.

### Solving quadratics by completing the square 2

PRACTICE PROBLEMS
Find the roots of a quadratic by completing the square. The numbers are a bit less convenient than they are in level 1.

### How to use the quadratic formula

VIDEO 16:32 minutes
Introduction to using the quadratic formula.

VIDEO 7:44 minutes

PRACTICE PROBLEMS
Use the quadratic formula to find the roots of a quadratic function.

### Example: Complex roots for a quadratic

VIDEO 10:15 minutes
Complex Roots from the Quadratic Formula

### Quadratic formula with complex solutions

PRACTICE PROBLEMS

VIDEO 10:14 minutes