Question

Which undefined terms are needed to define parallel lines?

Point, line
Line, plane
Coplanar, line
Point, coplanar

Answer 1

To define parallel lines, the most relevant undefined terms are **line** and **plane**. Parallel lines are defined as lines that are in the same plane and do not intersect, meaning they maintain a constant distance apart. Therefore, the correct choice from your list is:

**Line, plane**.