B Is Figure a Polygon? Examining Edges of the Image

AI Thread Summary
The figure in question can be classified as a polygon, but it is not a "simple polygon" due to its self-intersecting nature. The middle line segment is considered two edges, and the polygon can be described using various point labels, such as ABCBDECA or ABCEDCDA. For a shape to qualify as a polygon, it must close the loop by returning to the starting point. The discussion highlights the importance of defining what constitutes a polygon, particularly regarding intersecting edges. Overall, the classification of the figure hinges on the interpretation of these geometric rules.
Suyogya
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Can someone please tell is this (https://ibb.co/stGFSKs) figure a polygon. If yes then is the middle line would count as an edge?

15487814949745525543992389032260.jpg
 

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Yes, it could be described as a polygon - but not a "simple polygon".
https://en.wikipedia.org/wiki/Polygon

If the left edge from top to bottom is A, B, D and the right edge from top to bottom is A, C, E:
Then this could be described as polygon ABCBDECA or ABCEDCDA.

Thus, it would be a polygon that intersects itself.
polygons that do not intersect themselves are called "simple polygons".

Oh, and to answer your follow-on question: The middle line segment would be two edges.
 
.Scott said:
Yes, it could be described as a polygon - but not a "simple polygon".
https://en.wikipedia.org/wiki/Polygon

If the left edge from top to bottom is A, B, D and the right edge from top to bottom is A, C, E:
Then this could be described as polygon ABCBDECA or ABCEDCDA.

Thus, it would be a polygon that intersects itself.
polygons that do not intersect themselves are called "simple polygons".

Oh, and to answer your follow-on question: The middle line segment would be two edges.
let be name the points as,(https://ibb.co/2srLjB1) if AC would be an edge then A and C are vertices and segments BC, AC, AD, CE became edges. Is this justified Also for a simple polygon there should be no self intersecting edge, the line AC just touches the lines BD and BE, is this sufficient to fulfill the intersecting condition?
 
.With your new point labels, the polygon would be either BACADECB or BADECACB.
In order for it to be a polygon, you need to close the loop - end at the same place you started.
I am not sure I am interpreting your statements correctly, but it doesn't sound as though you are following that rule.
 
Suyogya said:
Can someone please tell is this (https://ibb.co/stGFSKs) figure a polygon. If yes then is the middle line would count as an edge?
To me, the question isn't answerable: either you define a polygon one way or the other, either allow straight angles or don't.
 
.Scott said:
.With your new point labels, the polygon would be either BACADECB or BADECACB.
In order for it to be a polygon, you need to close the loop - end at the same place you started.
I am not sure I am interpreting your statements correctly, but it doesn't sound as though you are following that rule.
thanks for correcting
 
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