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I apologize for asking about an incredibly simple math concept but I'm trying to brush up on my algebra and Googling hasn't helped, I don't know the name of the rule I am looking for.

According to a problem I've been walking through step-by-step on Wolfram Alpha if I have a fraction like this:

$$ \frac{a – x}{ax(x - a)} $$

I can factor out a -1 from the demoninator and it becomes:

$$ \frac{a – x}{ax*-1*(a - x)} $$

The order of a and x was somehow reversed, apparently this is just a rule in algebra. Can somebody tell me the name of the rule so I can learn more about it? Thanks in advance!

cirpis
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Irresponsible Newb
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1 Answers1

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This isnt a rule, its a property of the inverse of a element: $$(a-b)=-(b-a) = -1*b-1*(-a)=a-b$$ this can be seen simply by opening the parenthesis and multyplying each member by $-1$ or in other words changing the signs

cirpis
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