I needed to make an animation of Kate Nowak's visual pattern (
at Fawn Nguyen's site), and thought I would make it so you could generalize and see a few other patterns.
Secant and tangent lines
Fibonacci Numbers and the Fibonacci Spiral
Solution of a right triangle
Exploration 2 - Proportionallity with 3 Lines
Transformations of Parabolas
Conic Section Explorations