1. 6.2 Quadratic
Functions –
Vertex Form

2. What is a Quadratic
Function?
In a quadratic function the
highest power of x is 2.
 This means: quadratic functions have
an x2 term
Examples:
y = x2
y = 2x2 + x – 1
y = - x2 + 7

3. Our Parent Graph
Use y = x2 as the parent graph
x y
-3
-2
-1
0
1
2
3 “Parabola”

4. Vertex Form
Vertex form uses transformations
we already know on the parent
graph y = x2.
y = a(x – h)2 + k

5. Graphing Vertex Form
1. Sketch parent graph
2. Perform vertical
stretch/shrink and reflection
(as needed)
3. Shift (as needed) to create
final graph

6. Example 1:
Graph y = 2x2. Identify the
vertex and axis of symmetry.

7. Example 2:
Graph y = ½ x2 - 5. Identify the
vertex and axis of symmetry.

8. Example 3:
Graph y = -(x + 2)2 + 3. Identify
the vertex and axis of symmetry.

9. You Try!
Graph y = -2(x – 4)2. Identify the
vertex and axis of symmetry.