Why a Negative Number Times a Negative Number Equals a Positive Number

bernard beecher


One of the most mysterious mathematical topics taught in any elementary mathematics classroom is the concept that a negative time a negative equal a positive. This fundamental mathematical idea is listed in most elementary algebra text books as a rule without any justification for the validity of the rule. In this paper, I will present numerous mathematical arguments that attempt to justify this concept.


Negative and Positive Numbers;

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DOI: http://dx.doi.org/10.3968/6557

DOI (PDF): http://dx.doi.org/10.3968/pdf_13


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