Draw the figure, get the mathematics. GXWeb, a free mathematical modeling program, combines sketch-based drawing tools and…
https://geogebra.org/
Fascinating Earthbound Objects
http://mathstud.io/
https://geogebra.org
http://alexeev.org/
Bailey Dalton
http://sketchometry.org/
Declan Moore
https://mathkeyboards.com
