Can You Create Squares of Integral Areas on an 8x8 Grid Using Strings?

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Discussion Overview

The discussion revolves around the problem of forming squares with integral areas from 1 to 9 on an 8x8 grid using strings or rubber bands. Participants explore the feasibility of creating such squares and the geometric implications of their configurations.

Discussion Character

  • Exploratory
  • Mathematical reasoning
  • Conceptual clarification

Main Points Raised

  • One participant notes that squares with areas 1, 4, and 9 are trivial to form, while expressing confidence in forming squares with areas 2, 5, and 8, suggesting these are the only possible areas based on the sums of two squares less than 10.
  • Another participant draws a parallel to the "Traveling Salesman" problem, implying that the combinations of configurations may be complex and numerous.
  • A different participant discusses the requirement for the side length of a square to be the square root of the area, emphasizing that this necessitates the distance between two lattice points to be expressible as a sum of two squares.

Areas of Agreement / Disagreement

Participants express varying levels of confidence regarding the ability to form squares of certain areas, with some asserting that specific areas can be formed while others suggest that the problem may be more complex than initially thought. No consensus is reached on the overall feasibility of forming all specified squares.

Contextual Notes

Participants acknowledge the mathematical constraints related to the distances between lattice points and the conditions under which squares can be formed, but do not resolve these complexities.

Who May Find This Useful

This discussion may be of interest to educators, geometry enthusiasts, and those exploring combinatorial geometry or mathematical problem-solving techniques.

imathgeek
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Hi there,

I am a new person here, so I hope that you can understand this problem as I have written it. Suppose that you have an 8 by 8 grid (like a geo board) where at the intersections of the line segments are posts whereby you may run a string or rubber band about and make all sorts of geometric shapes.

"On the 8 by 8 grid can you form squares with a string or rubberband such that the squares have integral areas from 1 through 9? The lines needn't be horizontal or vertical in order to do this. If possible, how do you form your squares on the grid to achieve the desired area? If not possible, provide a proof showing why it cannot exist."

This is a problem I posed to my geometry students and I have received all sorts of answers. I am looking to verify my own work on the problem. Yep, I am a new professor and gave a problem that I didn't have an answer to.

I know that squares of areas 1, 4 and 9 are trivial. I can place squares with areas 2, 5, and 8. Since these are the only sums of two squares less than 10, these should be the only squares possible.

Any suggestions would be greatly appreciated.

Thanks.

imathgeek
 
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The variety of combinations is similar to the myriad "Traveling Salesman" solutions. Go Google on "traveling salesman".
 
I guess that I could look at the certain discrete values of the perimeter if that is what you're implying.

Thanks for the assistance. After reading your many posts this afternoon, I had a feeling that you would have something constructive to add to the problem.

Ken
 
To form a square of area A you need a side of sqrt(A)

To form a side of sqrt(A), it must be the distance between two lattice points, so there are integers B and C with A = B^2 + C^2, so your hypothesis is correct.

Hurkyl
 

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