All participants demonstrated the ability to recognize the affordances of the tool, while
their mathematical and technological activity ranged from an elementary and less
powerful to an advanced and more sophisticated activity. The data suggest that the
differences found are strongly related to the dynamic nature of the mathematical
representations afforded by the tool, in depicting the problem conditions. For example,
the introduction of additional free elements to the figure led to powerful
understandings of the problem, and to generalization. In one production, the invariance
of the area is not only numerically recognised but also geometrically explained; in
another situation the free elements allow seeing the answer as a particular case of a
more general statement; yet another case makes the problem even wider by extending
the several conditions stated and allowing the exploration of a more general problem.