There are so many undefined words which should be knowledge.
They are consistent because they deal with two different situations i.e.,
(i) If two points A and B are given, then there exists a third point C which is lying in between A and B on the line.
(ii) If two points A and B are given, then we can take a point C which don’t lie on the line passing through the point A and B.
These postulates do not follow Euclid’s postulate.
However, they follow axiom Euclid’s postulate 1 stated as "through two distinct points, there is a unique line that passes through them."