Construct Slider a with parameters of -20 to 20
Construct Slider h with parameters of -20 to 20
Construct Slider k with parameters of -20 to 20
In input bar type f(x)=a(x-h)^2+k
In input bar type V=(h,k), have V show name and value.
Create text box that says Vertex Form:y=f and f is an object.
Fix slider a, h, and k and text box in place.
Have fun and you can change colors and style etc.
