Geometry for Elementary School/Lines
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< Geometry for Elementary School(Redirected from Geometry for elementary school/Lines)
| Geometry for Elementary School | ||
| Points | Lines | Constructing equilateral triangle |
Contents |
[edit] Lines
A line is as wide as a point, infinitely thin, having an infinite number of points, (in a straight row), extending forever in both the directions. Any two lines can intersect at only a single point.
[edit] Line segments
A line segment is a part of a line, which has two endpoints. The endpoints give the line segment a fixed, or finite length.
Line segments A B, and C D, can be written as 
, and 
[edit] Rays
A ray is a line that has only one endpoint. A ray is infinite in one direction.
[edit] Axiom: there is only a single straight line between two points
Axiom: there is only a single straight line between two points.
- show by halving that there are infinite number of points in a line
- show that the number of points in a long line and a short line is equal
