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How does [(5/2)x^-2/(-2) simplify to (5/4)x^-2? watch

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    How does this:
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    Simplify to this:
    Attachment 594968594970 Can you explain to me please? I don't get how it simplifies to that.
    Thanks
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    The way I would have thought is that the 5/2, the 2 goes down to the bottom and is multiplied by the denominator, making the new denominator -4. (so it being -(5x^-2_)/-4
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    Multiply numerator and denominator by -2
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    (Original post by RogerOxon)
    Multiply numerator and denominator by -2
    How do you know to do that in order to get rid of the denominator? I thoought the rule in something like this was to bring the numerator of the fraction in the denominator over to the bottom and multiply that by the denominator.
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    First, consider that a/-b is identical to -(a/b). Therefore, our new expression is (5/2)(x^-2)/2. Try writing 5/2*x^-2 in fraction form, and see how you can apply fraction rules to simplify it.
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    (Original post by RogerOxon)
    Multiply numerator and denominator by -2
    When I multiply the numerator by -2, I get 10/2x^-2? What am I doing wrong?
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    (Original post by blobbybill)
    When I multiply the numerator by -2, I get 10/2x^-2? What am I doing wrong?
    That's right. You can divide 10 by 2.

    Now you need to do the same to the denominator, so that you're not changing the value (ratio).
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    (Original post by blobbybill)
    When I multiply the numerator by -2, I get 10/2x^-2? What am I doing wrong?
    Assuming you mean 10*2x^-2, nothing. Continue evaluating it.
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    (Original post by _gcx)
    Assuming you mean 10*2x^-2, nothing. Continue evaluating it.
    No, they don't. That is the numerator multiplied by -2.
 
 
 
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