Here's the question you clicked on:
lyns
Determine the slope of y=2x^2-4x+2.
its a porabola....can't have a "slope" :)
take a look yourself: http://www.wolframalpha.com/input/?i=y%3D2x%5E2-4x%2B2
You deferentiate the equation : It becomes : Gradient / Slope =4x - 4 Gradient and slope are the same thing.
JadeEyes is assuming you are studying calculus and is correct but if you are not in calculus then yummydum is correct it does have a scale factor of 2 if you are studying transformations
and that is 2x-4 which is dy/dx