mathematics - How to name the diagonals of a square so one can be told from the other?


A square has two diagonals, so how can I to name the separate diagonals if I want to distinguish one from another?


I mean something like the up to down diagonal and the down to up diagonal. Do you have any better suggestions?



Answer



You could borrow a term from heraldry and call them the diagonal dexter and the diagonal sinister. The dexter diagonal would be the one from upper left to lower right, and the sinister diagonal the other one. (In heraldry these things are bends).


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