1. 9.3 Graphing Quadratic Functions

2. Parabola: is a U shaped graph that represents a quadratic
If the leading coefficient is positive, the parabola will open up and look like a U
If the leading coefficient is negative, the parabola will open down and look like a n

3. Vertex: is the point where the parabola changes direction.

4. Axis of Symmetry
Axis of Symmetry: is an imaginary line that passes through the vertex of the parabola dividing the graph into 2 symmetric parts
Axis of Symmetry

5. Formula The formula for the axis of symmetry is:
Remember the formula for a quadratic equation is:
1) Find the Axis of Symmetry (A.S) for the following equation
a= 1
b= -2
c= -3

6. Your Turn Find the Axis of Symmetry for the following equations
A.S = 0
A.S = -2
A.S = -1

7. Graphing a Quadratic Function
Steps
1. Find the Axis of Symmetry
2. Make a table for x and y values. Placing the Axis of Symmetry (A.S) in the middle.
3. Choose 3 x-values less then the A.S and 3 x-values greater then the A.S
4. Find the corresponding y-values for the graph.
5. Plot the points and connect them with a smooth curve. X Y
A.S

8. Switch to Smart Notebook
For Graphing