Answer:
a. they are equal.
Step-by-step explanation:
Parallel lines are two lines that have no point in common, or are coincident. Two lines, contained in a plane, are parallel if they are either one and the same line (they are coincident lines) or, conversely, do not share any points. Similarly, in space, two planes are parallel although they are one and the same plane or do not share any points.
Axiom of uniqueness
The axiom that distinguishes Euclidean Geometry from other geometries is as follows: On a plane, through an external point to a line, one passes and only one parallel to that line.
Parallel lines are those lines that are in the same plane, have the same slope and that do not present any point in common, this means that they do not cross, do not touch and will not even cross their extensions. One of the most popular examples is that of a train tracks.
- Two lines are parallel if their director vectors are parallel, that is, if they are linearly dependent.
- Two lines are parallel if they have their equal director vectors.
- Two lines are parallel if they have their equal slopes.
- Two lines are parallel if the coefficients of x and y are proportional.
- Two lines are parallel if they form an angle of 0º.
