Euclids Elements - Book 1 - Proposition 01

The very first proposition, in which Euclid creates a equilateral triangle from a straight line by using two circles.

Tags: Euclid, Elements, Geometry, Equilateral, Triangle

Four Bar Linkage

You can drag the vertices of the shadow linkage to alter its geometry. Can you create a linkage which draws a figure 8?  How about the letter D?  How close to a straight line can you get? If you like this, you might like my 4 bar linkage clock app.

Tags: 4-bar-linkage, curve