Question

Which of the following statements is not a postulate? Options:

a. A plane contains at least three points not on the same line.
b. Points that lie on the same plane are said to be coplanar.
c. Through any two points, there is exactly one line.
d. If two lines intersect, then their intersection is exactly one point.

Answer 1

The statement that is not a postulate is: Points that lie on the same plane are said to be coplanar.

Step-by-step explanation:

Out of the given options, the statement that is not a postulate is option b: Points that lie on the same plane are said to be coplanar.

A postulate is a statement that is assumed to be true without proof in geometry. It serves as a foundation for developing geometric concepts and theorems.

Option b is incorrect because it is a definition rather than a postulate. It defines the term 'coplanar', which means that points lie on the same plane. Definitions are used to describe or name mathematical concepts, while postulates are assumptions taken to be true.