SOLUTION: X^2-3x-4/X^2-16 / 3x+3/X^2+9x+20 please help thank you inadvance

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Question 201759: X^2-3x-4/X^2-16 / 3x+3/X^2+9x+20 please help thank you inadvance
Found 2 solutions by RAY100, jsmallt9:
Answer by RAY100(1637) About Me  (Show Source):
You can put this solution on YOUR website!
( x^2 -3x -4) / (x^2-16) / (3x+3) / (x^2 +9x+20)
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{ (x^2 -3x-4) / (x^2 -16)} * { (x^2 +9x +20)/ (3x+3) } ,,,invert and multiply
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factor
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{ (x+1)(x-4) / (x+4)(x-4) } * { (x+5)(x+4) / 3 (x+1) }
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simply by canceling like terms
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(x+5) / 3
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check, let x=0,, original and answer = 5/3,,,ok

Answer by jsmallt9(3758) About Me  (Show Source):
You can put this solution on YOUR website!
Please put parentheses around each numerator and each denominator. Without them there are way too many ways to interpret:
X^2-3x-4/X^2-16 / 3x+3/X^2+9x+20

I'll give you some general tips:
  1. If division of fractions is indicated, change the division to multiplying by the reciprocal of the second fraction
  2. Factor the numerators and denominators.
  3. See if the fractions will reduce by canceling common factors (remembering to "cross cancel" if there fractions being multiplied).
  4. If fractions need to be added or subtracted
    1. You will need common denominators of course.
    2. The Lowest Common Denominator (LCD) will be the product of all the different factors in the various denominators.
    3. To turn each denominator into the LCD, multiply the numerator and denominator of each fraction by whatever factors of the LCD are "missing" from its denominator, if any.
    4. Multiply out the numerators but leave the denominators factored (so we can reduce the answer later more easily).
    5. Now that the denominators are the same, add or subtract the numerators.
    6. Factor the new numerator, if possible
    7. Reduce your final fraction by canceling common factors, if any
    8. After reducing, multiply out any numerators or denominators are still factored