Because AC = 3ab, the bisector of ∠ A intersects BC and D. From the nature of the angular bisector, CD/BD=3/ 1. DE∨AC, DF∨AB, so AC/CF=4/3, EB/BA= 1/4. According to Menelaus theorem, AC/CF FG/GE EB/BA = 1, so FG/GE=3, so GE= 1/2EF.