HG 32
A16. Pasch's Axiom. Given any triangle ABC. If L intersects AB in a point between A and B, then L also intersects either side AC or BC. If C does not lie on L, then L does not intersect both AC and BC.
T49. There exists a triangle whose angle sum is less than 180°.
T50. The angle sum of every triangle is less than 180û.