Through any two points, there is exactly one line
Through any three points not on the same line, there is exactly one plane
A line contains at least two points
A plane contains at least three points not on the same line
If two points lie in a plane, then the entire line containing those points lies in that plane
If two lines intersect, then their intersection is exactly one point
If two planes intersect, then their intersection is a line
Congruence of angles is reflexive, symmetric, and transitive.
Angles supplementary to the same angle or to congruent angles are congruent.
Angles complementary to the same angle or to congruent angles are congruent.
Perpendicular lines intersect to form four right angles.
All right angles are congruent.
Perpendicular lines form congruent adjacent angles.
If two angles are congruent and supplementary, then each angle is a right angle.
If two congruent angles form a linear pair, then they are right angles.