The usage of digital media, especially tablet apps, is currently a major concern in educational settings. A controversial discussion is also taking place in relation to mathematics education at primary schools. While on the one hand there are empirical findings on helpful isolated examples and related subject-didactic potentials of digital media,…

The paper's aim is to note a remarkable (and apparently unknown) relation for right triangles, its generalisation to arbitrary triangles and the possibility to derive these and some related relations by elimination using Groebner basis computations with a modern computer algebra system. (Contains 9 figures.)