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Re: Simplifying Algebraic Expressions with Subtracted Expressions
Posted:
Nov 13, 2013 7:40 PM


It depends on whether you want a child to understand the story being described by the expression (pedagogy) or wave the magic voodoo wand (mathematics).
If you have three apples and take away one apple, the voodoo magic approach is to add a negative apple.
Of course any opinion about good or bad advice depends on the context of the lesson and the age of the student.
Too much voodoo magic mathemagics is done without having established foundations built upon concrete instantiations that match symbolic expressions.



