It's called "KSEG". Ask your synaptic package manager to look for it, and while at it also install "KIG", a similar toy. After opening KSEG, look at "help" and read. After 10 minutes you ought to be able to reproduce a moving picture of the Theorem of Pappus.
KSEG is very similar to Geometer's Sketchpad, though it can easily output your diagrams in image formats such as PNG or BMP. KIG can do more advanced geometric figures, such as ellipses and parabolas.
Back to Prof. Walther MA460 page.
