Question

which figure represents an undefined term?

Explanation:

Step1: Recall undefined terms in geometry

Points, lines, planes are undefined.

Step2: Analyze each figure

The first figure is a ray (extends infinitely in one direction), second is a line - segment (has two endpoints), third is an angle (formed by two rays with a common endpoint), fourth is a line (extends infinitely in both directions). Rays are related to the undefined term of a line.

Answer:

The first figure (a ray with endpoints \(X\) and \(Y\) where the arrow - head indicates it extends infinitely in one direction) represents an undefined term. In geometry, points, lines, and planes are undefined terms. A ray is a part of a line which is based on the undefined term of a line.