1. 10-2 Graphing Quadratic Functions

2. Quadratic Functions (y = ax 2 +bx+c) When a is positive, When a is negative, When c is positive When c is negative the graph opens up the graph opens down the graph moves up. the graph moves down.

3. Use your graphing calculator and draw a conclusion about what happens when b changes…

4. The axis of symmetry changes when the “b” value changes. changing “a”, “b”, and “cchanging “a”, “b”, and “c”

5. Solving Quadratic Functions (ax 2 + bx + c = 0) by Graphing Identify the vertex Find the x-coordinate of the vertex, the formula for this is: Find the y-coordinate by substituting the x-value into the function Make a function table, using x-values to the left & right of the vertex. Plot the points and connect them

6. Solving Quadratic Functions (ax 2 + bx + c = 0) by Graphing Example: Sketch the graph of Find the x-coordinate of the vertex= = 1 Find the y-coordinate of the vertex (plug in 1 for the x-coordinate) Graph the vertex (1, -4) *note a = 1, b = -2, c = -3

7. Make a function table, using x-values to the left & right of 1 (the vertex) xy 0 1 2 3 0 -3 -4 -3 0 Plot the points and connect them. Graph the vertex (1, -4)