# A curious walk through the Coordinate Plane

While I was doodling, I discovered something interesting regarding drawing a walk in the coordinate plane.

First, I selected 4 random lattice points as the vertices of a quadrilateral. Then, I started on a certain vertex. Next, I drew a line segment to the next vertex (going clockwise), then continued the line segment to have the extension be equal in length to the original line segment. Next, I did this again with the next vertex, drawing from where I was to the vertex, then drawing another line segment equal in length to my previous segment.

I noticed that whenever my original quadrilateral was a parallelogram, my path was bounded. However, if it wasn't a parallelogram, then my path became unbounded, growing indefinitely.

I tried the experiment again, except instead I chose a random point on the plane to start. Same results.

What do you guys think? Can you prove this conjecture? I managed to link this with another similar problem that is easy to prove. Can you find that problem?

Note by Daniel Liu
7 years ago

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Can you add a picture to go with your description? That will make following your instructions much easier.

Even an example in the case of a parallelogram could shed some light immediately as to why it would be bounded.

Staff - 7 years ago

It will be good if you post a picture of this as well :p .....

- 7 years ago