$ sudo apt-get update
$ sudo apt-get install geogebra-kde 

geogebra-kde is installed in your system.

Make ensure the geogebra-kde package were installed using the commands given below,

$ sudo dpkg-query -l | grep geogebra-kde *

You will get with geogebra-kde package name, version, architecture and description in a table

geogebra-kde package basic information: