When putting a quadratic equation in vertex form, I am having difficulty understanding why $h$ is negative when the location of the parabola goes to the right... why is this?
For example, if I have... $y = -2(x-2)^2+9$
I understand that
- $a$ is -2, which means that it is a down-facing parabola
- $k$ is 9, which means that its vertex is positive and above the x-axis
I do not understand that since $k$ is negative, that means the location of the parabola is on the right side of the graph? Shouldn't it be on the left side, since it is negative? Also, when using a Flash quadratic graph displaying tool, it produces these results:
When I specify $h$ to be positive, it comes out to be negative in the quadratic equation. What's up with this?