MEDIAN, ALTITUDE and PERPENDICULAR BISECTOR
MOVE points A,B and C to verify that, for any △ABC : 1) BD = CD (means AD is a median of △ABC), 2) ⦣AEC = 90° (means AE is an altitude of △ABC) , 3) ⦣FDB = 90°, such that BD = DC (Means FD is a perpendicular bisector of BC).