Quadratic Functions
by London Fleming
Graph 1
Function: y= x^2+6x+8
(Minimum)
- Y-intercept: (0,8)
- X-intercepts: -2 and -4
- Domain: All Real Numbers
- Range: y> -1
- Axis of Symmetry: x= -3
Graph 2
Function: -x^2+8x-12
(Maximum)
- Y-intercept: (0, -12)
- X-intercepts: 2 and 6
- Domain: All Real Numbers
- Range: y< 4
- Axis of Symmetry: x= 4
Up or Down?
The equation for a quadratic function is:
y= ax^2 +bx + c
If the a value is a negative the graph opens down.
If the a value is a positive the graph opens up.
Vertex?
The equation for the vertex is:
(-b/2a, f(-b/2a) )