26-Mar-1995
## Unsolved Problem 13:

##
Is there a point in the plane that is at a rational
distance from each of the four corners of a unit square?

A rational number is a number that is the
ratio of two integers.

A *unit square* is a square of side length 1.
## Reference:

- [Boroczky 1987]
- K. Böröczky and G. Fejes Tóth,
Intuitive Geometry.
North-Holland Publishing Company. New York: 1987.
Page 696.

Rational Distances to the Vertices of a Square

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are investigating. We do not suggest that you tackle these problems,
since mathematicians have been unsuccessfully working on these
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