GoGeometry Action 95!

Creation of this applet was inspired by a tweet from Antonio Gutierrez (GoGeometry). In addition to proving that the pink point is the midpoint of this segment drawn parallel to both bases, prove that this segment has a length equal to the harmonic mean of the trapezoid's base lengths. Recall the harmonic mean of 2 numbers a and b is defined to be the reciprocal of the average (arithmetic mean) of these numbers' reciprocals. In essence, the harmonic mean of a and b = = .