N-Gon Approximating a Circle

This n-gon (regular polygon of n sides) has a variable number of sides. Changing the value for n demonstrates very visually how regular polygons of increasing numbers of sides, with the same radius, have a shape that increasingly approaches that of a circle.

Tags: N-gons, circles

Tridecagon Diagonals, Circles and Tangents

You'll want to start out with the heptagon and work your way up. This one's the same as all the others, just with a 13-sided regular polygon. Observe the tangencies to diagonals of circles centered at intersections of diagonals, when the circles are resized (by dragging). This is a smaller version that works well on most monitors (zoom in with two-finger touch). Bigger version here.

Tags: Tridecagon, diagonals, circles, tangents, intersections, puzzler, intricate, confusing, wow