Question

three undefined terms in mathematics
i point
ii line
iii plane
the mathematical term parallel lines explicitly uses the
undefined term(s)
the mathematical term perpendicular lines explicitly
uses the undefined term(s)
the mathematical term line segment explicitly uses the
undefined term(s)

Explanation:

• Parallel lines are defined as lines that do not intersect. The key undefined term here is "Line" as the definition is based on the concept of lines.
• Perpendicular lines are defined as lines that intersect at a right - angle. Again, the fundamental undefined term is "Line" since the definition is about the relationship between two lines.
• A line segment is defined as a part of a line that has two endpoints. So, it explicitly uses the undefined terms "Line" (to refer to the larger set of which it is a part) and "Point" (for the endpoints).

Answer:

• Parallel lines: Line
• Perpendicular lines: Line
• Line segment: Line and Point