Second Degree Equations
by Dorothy Evans
Letís examine the equation
on the same axis using different values for d.
First letís examine the parent function.
Notice the vertex lies on the origin (0, 0)
Now letís see what the graph looks like when d from our original equation is 0.
What do you notice about the graph of the equation compared to the parent graph?
Q: Did every point on the graph move or did the graph stretch down?
You should notice the vertex of the parent graph has moved down 2 to the point (0,-2).
Now letís see what happens when we make d = 2
What happened in the new graph (purple)?
The graph moved right 2
So what do you think will happen if d = 6?
Thatís right the vertex moved right 6 spaces to (-2, 6)
What would happen if we made d = -4?
Can you guess?
Scroll down to see
Can you make any conjectures from this demonstration about how a change in d in the equation †affects the graph?
What would you conjecture?† Test your hypothesis on another graph such as