The figure shows a triangle ABC, BE is
the median and BH the altitude. If AB = c, BC = a, AC = b and EH
= d prove that .
Geometry software that can be used to learn and research:
Geometry Expressions, Cabri, Cinderella, GeoGebra, Geometer Sketchpad, C.a.R., TracenPoche, Mathematica.
Median length, Apollonius' Theorem
Euclid's Elements Book II Proposition 13