1. Graph Quadratic Functions in Vertex or Intercept Form
Notes 4.2 (Day 2)
Graph Quadratic Functions in Vertex or Intercept Form

2. Intercept Form:
The x-intercepts are p and q (both are the opposite of what you think they are)
The x-coordinate of the vertex is halfway between p and q
If a is positive the graph opens up and holds water
(vertex is a minimum)
If a is negative the graph opens down and spills water
(vertex is a maximum)

3. How to graph a quadratic in Intercept Form:
Step 1: Find the x intercepts (p, 0), and (q, 0)
Step 2: Find the x-coordinate of the vertex
Step 3: Plug the x-coordinate of the vertex into the equation to find the y-coordinate of the vertex
Step 4: Plot the intercepts and vertex on the graph and connect the points with a curve

4. Graph.

5. Graph.

6. Graph.

7. Standard Form:
To put an equation into standard form, simplify the right hand side of the equation.

8. Write the equation in standard form.

9. Write the equation in standard form.

10. Write the equation in standard form.

11. Write the equation in standard form.

12. How to findthe minimum or the maximum value of a function:
Step 1: Find the vertex starting with the x-coordinate. ( , or depending on which form the quadratic is in.
Step 2: Plug the x-coordinate into the equation to find the y-coordinate of the vertex.
Step 3: Look at the a value. If it is positive, the graph holds water and is a minimum.
If it is negative, the graph spills water and is a maximum.

13. Find the minimum or the maximum value of the function.

14. Find the minimum or the maximum value of the function.

15. Find the minimum or the maximum value of the function.

16. Find the minimum or the maximum value of the function.

17. Homework
P , 24-41