More is in the brew, solving for iso-curve.
Not doing as exemplified would complain NO real roots.
These two examples are simple lecture guide line, ToolBox.



Contour SOLVE Circular Code Ellipse.sm (54.55 KiB) downloaded 1101 time(s).
Contour SOLVE Circular Code Electron.sm (52.7 KiB) downloaded 1112 time(s).