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Rational expressions very simble, but hard for me

  1. Apr 2, 2008 #1
    [tex] \frac{5x-5y-bx+by}{5x-5y+bx-by} [/tex]

    i can't cancel anything

    i can't factor anything

    please help
  2. jcsd
  3. Apr 2, 2008 #2


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    do the same with b
  4. Apr 2, 2008 #3
    but the b's (x and y) doesn't cancel since they have two different signs
  5. Apr 2, 2008 #4


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    -bx+by=(-b)(x-y). (x-y) IS a factor of both the numerator and the denominator.
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