# Interactive parabola graphs

By Murray Bourne, 05 Dec 2011

I've just added some new interactive graphs which demonstrate some of the key features of parabolas:

• A parabola is the locus of points equidistant from a point and a line
• The effect of moving the focus relative to the directrix (the parabola narrows or becomes wider)
• The equation of a parabola whose vertex is at (h, k) is given by (x − h)2 = 4p(y − k)
• A parabola with horizontal axis and its equation

I develop these interactives so readers can better understand the concepts and will see how the equations work.

Check it out and let me know what you think. Do the graphs help your (or your students') understanding? How could they be improved?

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