Parallel Postulate
If there is a line and a point not on the line, then there is exactly
one line through the point parallel to the given line.
Perpendicular Postulate
If there is a line and a point not on the line, then there is exactly
one line through the point that is perpendicular to the given line.
Segment/ Angle Addition Postulate
If B is between A and C, then AB+BC=AC. If AB+BC=AC, then B is
between A and C. Is the same with angles.