A plane algebraic curve
invented by Descartes
Although, it seems that Descartes was unable to sketch the
curve accurately. Challenge. Can you do better?
An equation for the curve is x3 + y3=3axy
(for a real number constant a).
This curve has a singular point at the origin.
history sourced from http://www-groups.dcs.st-andrews.ac.uk/~history