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Geometry

You will learn and explore the building blocks of Euclidean geometry by studying such things as line segments and points.

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After completing this tutorial, you will be able to complete the following:

- Know the definition of a line.
- Know that two points determine a line.
- Know the definition of collinear points.

What is the definition of a line segment?

~ A line segment is made up of two points on a line and all the points between them.

How do we name line segments?

~ A line segments is made up of two points on a line and all the points between them. To specify a line segment, we must be given two points on a line; these two points are called the endpoints of the line segment. We use the endpoints of a line segment to name the line segment. For instance, if the endpoints of a line segment are the points A and B on a line, then the line segment is named line segment AB.

What is the difference between a line segment and a line?

~ A line is a straight geometric figure whose length can be extended infinitely in opposite directions. A line segment is made up of two points on a line and all the points between them. Therefore, a line segment is a portion of a line. Moreover, a line has infinite length, whereas a line segment has finite length.

Look at your list of examples from question 2 in the previous section. Are these examples of lines or of line segments?

~ Answers may vary. It is likely that the examples listed in question 2 in the previous section are all examples of line segments because they likely have finite length. Some common examples of objects that can be modeled by line segments are pens, rulers, and straws.

Approximate Time | 2 Minutes |

Pre-requisite Concepts | Students should have a general understanding of the following terms: definition, collinear, and line. |

Course | Geometry |

Type of Tutorial | Animation |

Key Vocabulary | definition, collinear, line |