1. Match graph and equation Not all equations will have a graph
I can write a quadratic equation
from a graph.
Warm Up
Page 353 Problem 8-82
Match graph and equation
Not all equations will have a graph

2. B E A G D I

3. Homework Questions

4. Solve using Zero Product Property.
(𝑥+1)(𝑥−2) = 0
(𝑥−4)( 𝑥+1) = 0
(2𝑥−3)( 3𝑥+5) = 0
𝑥=−1 and 𝑥=2
𝑥=4 and 𝑥=−1
𝑥=3/2 and 𝑥=−5/3

5. Can you work backwards? x-int = ( -1, 0) x-int = (2, 0) 𝑦=(𝑥+1)( 𝑥−2)
𝑦= (𝑥 –4) ( 𝑥+1)

6. Now you try some . . . x-int = ( -3, 0) x-int = (1, 0) 𝑦=(𝑥+3)( 𝑥−1)
𝑦=(𝑥−2)( 𝑥+2)
𝑦=(𝑥−3)(𝑥+5)

7. Parabolas come in different shapes.
It is the leading coefficient that makes the difference!

8. What do you know about this graph?
x-int = (-2,0)
x-int = (1,0)
3rd Point = (0, 8)
𝑦= 𝑎 (𝑥+2)(𝑥−1)
We need to find a!

9. What do you know about this graph?
(0,8)
𝑦= 𝑎(𝑥+2)(𝑥−1)
Plug in (0, 8)
8= 𝑎( 0+2)(0−1)
8= 𝑎(2)(−1)
8= −2𝑎
−4 = 𝑎
𝒚 = − 𝟒(𝒙 + 𝟐)( 𝒙 – 𝟏)
𝒚 = − 𝟒 𝒙 𝟐 −𝟒𝒙+𝟖

10. Try One: 𝒚 = 𝟒(𝒙 – 𝟐)(𝒙 + 𝟎) 𝒚 = 𝟒𝒙(𝒙 – 𝟐) 𝒚 = 𝟒 𝒙 𝟐 −𝟖𝒙 x-int = (2,0)
3rd Point = (1, -4)
𝑦 = 𝑎(𝑥 –2)(𝑥+0)
−4 = 𝑎(1−2)( 1+ 0)
−4 = 𝑎 (−1)(1)
−4 = −𝑎
4 = 𝑎
𝒚 = 𝟒(𝒙 – 𝟐)(𝒙 + 𝟎)
𝒚 = 𝟒𝒙(𝒙 – 𝟐)
𝒚 = 𝟒 𝒙 𝟐 −𝟖𝒙

11. Remember Jen, from the water balloon problem . . .
Jen’s data
Remember Jen, from the water balloon problem . . .
Find the rule!

12. Finish Retake Problem Set