Question

Which figures can be precisely defined by using only undefined terms? Select three options.

angle
arc
circle
line segment
parallel lines

Answer 1

The figures that can be precisely defined using only undefined terms are:

1. **Circle** - A circle can be defined using the concept of a point (center) and distance (radius).
2. **Line Segment** - A line segment can be defined as part of a line that connects two endpoints (points).
3. **Parallel Lines** - Parallel lines can be defined as two lines that are in the same plane and do not intersect, based on the undefined terms of line and plane.

While angles and arcs can be discussed, they generally require additional definitions or concepts that go beyond only undefined terms. Therefore, the best choices are circle, line segment, and parallel lines.