Question

Consider the terms pyramid, line, square, and triangle. Which term is not defined in Euclidean geometry.

Answer 1

Answer: Consider the terms pyramid, line, square, and triangle. The term  line is not defined in Euclidean geometry.

Answer 2

The correct answer is:

line.

Explanation:

In Euclidean geometry, there are 3 terms that are considered "undefined":  point, line and plane. 

They are considered undefined because they are described, but not every formally defined.

The other terms in this question, pyramid, square and triangle, are all formally defined.