In a right angle triangle ABC, a line from B intersects the point D which is the midpoint of AC. Which statement is necessarily true if BD is an altitude to the hypotenuse of right triangle ABC?
1) ΔADB ≅ ΔBDC
2) ΔADB ∼ ΔBDC
3) AB/BC = AC/BD
4) ∠BAC ≅ ∠BDC
