Question

Which CANNOT be used in a proof?

A. Theorems
B.Postulates
C.Properties
D.Undefined Terms

Answer 1

Answer: D.Undefined Terms

Explanation:

The reason in a mathematical proof can be a given information, vocabulary definitions, properties, postulates or previously proved theorems.

But the undefined terms are the terms which used in geometry to define other terms.

Therefore , the undefined terms cannot be used in a mathematical proof .

Hence , D is the correct option.

Answer 2

The correct answer among the choices provided is option D. Undefined terms cannot be used as a proof in geometry. Undefined terms are the words that are not formally defined. The three words in geometry that are not formally defined are point, line, and plane.