Solving with multiple unknown variables & more

[Angus]

One can use the geometry App for plotting aswell. plotfunc() does the job.

The difference is that plotfunc() is for expressions. So maybe a frontend to exchange data between geometry app and cas would be helpful. I should try to start working on some program but my programming skills are still not sufficiant.
http://www.hpmuseum.org/forum/thread-3203.html
Here it is shown how to pass the data to the app variables. You would need to extract the Expression from the formula, of course.