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Viewing Version 6 of 'parallellism in Euclidean plane'
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Title of object: parallellism in Euclidean plane
Canonical Name: ParallellismInEuclideanPlane
Type: Definition

Created on: 2007-06-05 13:32:04
Modified on: 2007-08-28 04:42:51

Creator: pahio
Modifier: pahio
Author: pahio
Author: Mathprof
Author: Wkbj79

Classification: msc:51-01
Keywords: Euclidean geometry
Defines: parallel, parallel lines, parallelism
Synonyms: parallellism in Euclidean plane=parallelism
parallellism in Euclidean plane=parallelism in plane
parallellism in Euclidean plane=parallelism of lines

Revision comment (for changes between this and next version):

parent

Preamble:

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Content:

Two distinct lines in the Euclidean plane are {\em parallel} to each other if and only if they do not intersect, \PMlinkname{i.e.}{Ie} if they have no common point. By convention, a line is parallel to itself.

The {\em parallelism} of $l$ and $m$ is denoted
$$l \parallel m.$$

Parallelism is an equivalence relation on the set of the lines of the plane. Moreover, two nonvertical lines are parallel if and only if they have the same slope. Thus, slope is a natural way of determining the equivalence classes of lines of the plane.