Postulate

A statement whose validity is accepted without proof is called a postulate.

In addition to point, line plane etc, it is also necessary to start with certain other basic statements that are accepted without proof. In geometry these are called postulates.

A postulate, though itself is an unproved statement, can be cited as a reason to support a step in a proof. Postulates are just like axioms in arithmetic and algebra, that they are accepted without proof.

Below are some Postulates:

Postulate 1: A line contains at least two points.

Postulate 2: A plane has at least three non-collinear points with it.

Postulate 3: If we cross through any two points, there is exactly one line.

Postulate 4: If we cross through any three non-collinear points, there is exactly one plane.

Postulate 5: If two points lie in a plane, then the line joining them lies in that plane.

Postulate 6: If two planes intersect with each other, then their intersection is a line