- John Golden
A tool to divide up a quadrilateral into 4 subquadrilaterals. If the starting trapezoid is a pattern block trapezoid (congruent to 3 equilateral triangles), then the subdivision is a reptile into similar trapezoids. Make some art! Mine, and the image that inspired this, is at http://mathhombre.tumblr.com/post/50674144422/saw-this-great-image-at-peanos-from-elijah
More GeoGebra at mathhombre.blogspot.com.