Using GeoGebra to interpret the solution
Andreia, Lucas and José also sent a GeoGebra file and a brief text that seeks to validate
the conclusion obtained by manipulating their construction (Figure 3). They built a
rigorous and robust representation of the garden and the flowerbed, and added two
measures using the tools: the length of the
segment GH and the area of the triangle EGH.
It seems that the manipulation of the points G
and E, the observation of the invariance of the
area, and the length of the bottom side of the
triangle convince them that the areas do not
change, whatever triangle they represent under
those conditions.
In written, they try to explain the invariance of
the area: “triangles with the same base and the