1. The Quadratic Formula

2. y = ax 2 + bx + c (Standard Form) * To apply the formula, you must write the equation in standard form first! x 2 +5x = 14 (not in standard form) -14 x 2 +5x-14 = 0 (This is standard form.) This gives us the x-intercepts

3. Quadratic Equation:

4. x = 2,-7 x 2 +5x-14 = 0

5. To graph, find the vertex Plug back in for y.

6. Change -14 to ¼’s Y value is

7. Vertex is To graph, make mixed numbers y x -7 2

8. Practice saying the Quadratic Equation… Sing along with the clip!

9. Solve: 0= x 2 +2x-5 Clear out - in front of a by multiplying both sides by -1

10. AND Use calculator to find exact ≈1.45

11. Find Vertex and Graph Vertex (-1,6)

12. x y 6 -3 -4 12 Why does it open down? The original was a negative!

13. REAL LIFE: 1050 ft. If you throw a rock straight down from a cliff at a speed of 30ft./sec., how soon will it hit the ground?

14. Formula: h=-16t 2 +vt+s h= height at time t t= time in seconds s= starting height in feet v= velocity (ft/sec.) falling is - Set h=0 when rock hits ground 0=-16t 2 +vt+s 0=-16t 2 +(-30)t+1050

15. And

16. Can’t have - seconds