Lesson on solving quadratic equations using the quadratic formula -- and a song to remember it by.

1. 10.6 Solve Quadratic Equations using the ♫ Quadratic Formula ♫ Goal: to learn the quadratic formula, and solve equations using it.

2. We've solved quadratic equations by factoring --

3. We've solved quadratic equations using square roots--

4. We've graphed quadratic equations and identified the solutions on the graph. How many solutions are shown on each graph? y x y x y x

5. Try solving: What do we do when a quadratic equation doesn’t factor and it can’t be solved using square roots?

6. We SING!! … the quadratic formula song. ♫

7. The quadratic formula can be used to solve ANY quadratic equation that’s written in standard form:

8. The Quadratic Formula

9. http://www.youtube.com/watch?v=bSQ7nxjmXXg

10. How does it work? Put the coefficients of the variables into the formula.

12. Let’s try this equation again: First: what are the values of a , b , and c ?

13. Next: Replace the letters in the formula with the appropriate number, and then simplify.

15. Let’s try another one What are the values of a , b , and c? ( write it down, work together )

16. Substitute Simplify

17. Notice that we only had 1 solution. Why is that? Could we ever get no real solution? If so, when?

20. Assignment: pg 674 #4-26 even, 46 (Bonus pts for singing the QF song/ reciting the QF.) Monday – Spirit Day: “ Take me out to the ballgame” Chapter 10 Test: Thurs 3/17