1. Graphing Quadratic Equations
Lesson 10-1
Graphing Quadratic Equations

2. Definitions
Quadratic Function - can be written in the form of y = ax2 + bx + c, where a  0.
Parabola - The graph of a quadratic function is a parabola.

3. Parabola
positive
Negative

4. Equation of the Axis of Symmetry
The equation of the axis of symmetry for the graph of y = ax2 + bx + c, where c  0, is

5. 6 Steps to Graphing Quadratic Equations
Solve for line of symmetry using
Plug x value into original equation to find vertex (x,y).
Define vertex as a minimum or a maximum.
Find value of three numbers above and below line of symmetry value.
Plot points you have found.
Draw graph.

6. Use a table of values to graph y = x2 - x - 2.

7. Use a table of values to graph y = -2x2 + 2x + 4.

8. Consider the graph of y = -2x2 -8x -2.
Write an equation of the axis of symmetry.
Find the coordinates of the vertex.
Identify the vertex as a maximum or a minimum.
Graph.

9. x y