
Re: Is a rectangle a square?
Posted:
Oct 28, 2003 4:57 PM


On Tue, 28 Oct 2003, Walter Whiteley wrote:
> This is a 'standard' difficulty, and some elementary math > texts get this tangled up. > > The way mathematicians work, think, and use these words, > we are 'inclusive'. So something with four Equal sides > DOES have two pairs of opposite sides equal. > That means is also a rectangle.
Quite right! But let me point out that what this shows is that it's sensible to define "rectangle" so that it includes "square".
However, the question asked "is a rectangle a square?"
The correct answer to this is "not always". For example, a 2 x 1 rectangle certainly isn't a square, while a 1 x 1 one is.
John Conway

