Pre-Calculus Lesson 5: Solving Quadratic Equations Factoring, quadratic formula, and discriminant

Steps to Follow 1. Set the equation equal to zero. 2. Factor. 3. Set each factor equal to zero (set up a T-chart). 4. Solve.

Quadratic Formula

Discriminant  What is the formula for the discriminant?  What does the discriminant tell us about roots? ◦ If positive? ◦ If =0? ◦ If negative?

Discriminant  What is the formula for the discriminant?  What does the discriminant tell us about roots? ◦ If positive? ◦ If =0? ◦ If negative?

Discriminant  What is the formula for the discriminant?  What does the discriminant tell us about roots? ◦ If positive? ◦ If =0? ◦ If negative? 2 real roots

Discriminant  What is the formula for the discriminant?  What does the discriminant tell us about roots? ◦ If positive? ◦ If =0? ◦ If negative? 2 real roots 1 real root

Discriminant  What is the formula for the discriminant?  What does the discriminant tell us about roots? ◦ If positive? ◦ If =0? ◦ If negative? 2 real roots 1 real root 2 imaginary roots 0 real roots

2 real roots

0 real roots 2 imaginary roots