What makes a line parallel?

• A parallel line is a line that intersects another line at a 90° angle.
• A parallel line is a straight line that always remains the same distance from another line and never intersects it.
• A parallel line is a straight figure that has no thickness and extends infinitely in two opposite directions.
• A parallel line is the finite section of line between two points on that line.

1 answer

The correct statement that defines a parallel line is:

A parallel line is a straight line that always remains the same distance from another line and never intersects it.

Parallel lines, by definition, have the same slope (in a two-dimensional space) and will never meet, regardless of how far they are extended.