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 [ change | change source ]

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 [ change | change source ]

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

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Naming lines [ change | change source ]

Lines can get their names from any two points on the line. For example, if a line contains two different points, named ${\displaystyle A}$ and ${\displaystyle B}$, then the line can be called either ${\displaystyle {\overleftrightarrow {AB}}}$, or ${\displaystyle {\overleftrightarrow {BA}}}$.

Sometimes, lines are named with just one symbol. A letter such as ${\displaystyle \ell }$ might be used. ^{[1] [2] [3]}

Two lines [ change | change source ]

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.

Related pages [ change | change source ]

• Linear function
• Point (geometry)
• Plane (mathematics)

References [ change | change source ]

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 .