Parabolas in Vertex Form
Drag point P to explore how the values of the x and y of the plotted point vary along one particular parabola with fixed values for a, h, and k. Use the sliders to change the values of a, h, and k, which will change the parabola itself, allowing you to explore whole families of parabolas.
This applet is adapted from one of the activities in the Sketchpad curriculum module Exploring Algebra 2. The activity explores the roles of a, h, k, the vertex of the parabola, and the axis of symmetry.