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A line is a fundamental concept in geometry. You could say it is the baby steps of a complex world, which is geometry. A line segment is a portion of a straight line bounded by two points, called endpoints. Consider the below diagram:
There are two points, they are denoted by A and B. In order to join both points, you need to draw a line, we call that type of line a line segment because it fulfils both conditions. The first condition is the straight line, and the second condition is the two points. The line segment is denoted by the endpoints that limit it or a lowercase letter representing the line itself. There is not much rocket science in line segment that is why we called it baby steps because it is very simple and easy to understand. Let's understand the different types of line segments that you can encounter in geometry.
Equal Line Segments
If two lines are equal in length, no matter if they are parallel or not, they will be called equal line segments. That is why it is called equal line segments because both line segments are equal.
Consecutive Line Segments

Two consecutive line segments have a common endpoint. Consider the above image, you see that both line segments have a point common and that is point B. If two line segments share a common point, we can call them consecutive line segments.
Aligned Line Segments

Two consecutive line segments are aligned when they belong to the same line.
Operations with Line Segments
You can apply mathematical operations within two or more line segments. Below are all the mathematical operations that you can apply on different line segments with their procedure.
Adding Line Segments

Subtracting Line Segments

Multiplying a Segment by a Number

Dividing a Segment by a Number

Dividing a Segment into Parts
Divide the segment AB into 3 equal parts.

1. Draw a ray that shares the origin of point A with the line segment AB.

2. Mark in the ray 3 equal units starting from point A.

3. For each of the divisions of the ray, draw parallel lines to the segment joining B. The points obtained in the segment AB represent 3 equal parts.
Nice emma really precise information.. I appreciate u
Hey Raptor! Thanks very much for the positive feedback, very much appreciated!
I’m just curious if the area between the polygon and the circumscribed circle has a name.
https://www.superprof.co.uk/resources/academic/maths/geometry/plane/orthocenter-centroid-circumcenter-and-incenter-of-a-triangle.html