1. Solve each of the quadratic functions: x2 – 4 = 0 2. x2 - 2x – 8= 0
Warm-Up #1
Solve each of the quadratic functions:
x2 – 4 = 0
2. x2 - 2x – 8= 0

2. Unit 2 Day 6
Quadratic Formula

3. Have desks cleared to begin quiz!
Sheet of paper
Pencil
Calculator

4. Essential Question ( )
How can I use reasoning skills to determine which method to solve a quadratic function?

5. Ways to Solve Quadratic Equations and When to use each:
Factor – Use if you can easily determine the factors
Graphing – If you have access to a graphing calculator
Solving for x (Square root method) – Use if there is no “b” value
Quadratic Formula – ALWAYS works!

6. Square Root Method
We will use this method to solve a quadratic equation if the case is b = 0. or When this is the case, we solve first for x2 and then square root both sides. When you solve x2 = #, there are ALWAYS 2 Solutions for x, the positive and negative!

7. Example
Solve: 3x2 – 27 = 0

8. Solve these equations on your own:
x2 – 20 = 0
5x2 = 55
6x2 – 42 = 0

9. Can we solve this using factoring or solving square roots?

10. Quadratic Formula
Quadratic Formula: If , then: Find a, b, and c and plug into the formula. Then simplify. **Make sure you use Order of Operations when simplifying.
Add a hyperlink for the bottom

11. Quadratic Formula
The quadratic formula allows you to solve ANY quadratic equation,
USE WHEN YOU CANNOT FACTOR!
An important piece of the quadratic formula is what’s under the radical:
b2 – 4ac
This piece is called the discriminant.
The discriminant can tell you how many solutions your quadratic will have (Discuss Monday!)

12. #1 Solve using the quadratic formula

13. #1 Solve using the quadratic formula.

14. #3 Solve using the quadratic formula

15. Try to solve these on your own using the quadratic formula:

16. 3 Methods to Solve
We have talked about all three methods to solve a Quadratic Equation. “Three Options to solving Quadratic Equations” Worksheet Pick three problems from each column to solve. Check your solutions.