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Line

From Simple English Wikipedia, the free encyclopedia

A line is the path of one point that is moving. A line is a type of geometric figure. A line has length, but no width. A line is made up of an endless number of points.

Straight and curved lines

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This is a line that curves

A line can be straight or curved. In geometry, the word line means a straight line. A straight line is the shortest distance between two points. A straight line is traced by a point moving in a direction that does not change.

A curved line is sometimes called a curve. The edge of a circle is not straight. It is an example of a curve.

Line segments

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A line segment is part of a line. Here are examples of straight line segments:



_____   __

Naming lines

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Lines can get their names from any two points on the line. For example, if a line contains two different points, named and , then the line can be called either , or .

Sometimes, lines are named with just one symbol. A letter such as might be used.[1][2][3]

Two lines

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Two lines can be:

  • Parallel: Two lines are parallel if they are on the same plane and they never touch.
  • Concurrent: Two lines are concurrent if they touch on one point.
  • Coincident: Two lines are coincident if they are made of the same points.
  • Perpendicular: Two lines are perpendicular if they make four right angles where they touch.
  • Skew: In Euclidean space, two lines are skew if they are not parallel but they never touch.
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References

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  1. "Compendium of Mathematical Symbols". Math Vault. 2020-03-01. Retrieved 2020-08-16.
  2. Weisstein, Eric W. "Line". mathworld.wolfram.com. Retrieved 2020-08-16.
  3. "An introduction to geometry (Geometry, Points, Lines, Planes and Angles)". Mathplanet. Archived from the original on 2020-09-29. Retrieved 2020-08-16.