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Subtract the rational expression

Please show the steps to the answer

Subtract the rational expression Please show the steps to the answer-example-1
User Myy
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1 Answer

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29 votes

Answer:


(x^2-8x-12)/(2x^2+5x-4)

1. Find common denominator (LCD)

(x + 3)(2x - 1) =
2x^2 + 5x - 4

2. Multiply bottom to get LCD, then multiply top to match

First term:
(x)/(x+3) ((2x -1)/(2x-1) ) = (2x^2-x)/(2x^2+5x-4)
  • Second term:
    (x+4)/(2x-1) ((x+3)/(x+3) )=(x^2+7x+12)/(2x^2+5x-4)
  • Ending expression:
    (2x^2-x)/(2x^2+5x-4) -(x^2+7x+12)/(2x^2+5x-4)

3. Rewrite terms in a single fraction


(2x^2-x)/(2x^2+5x-4) -(x^2+7x+12)/(2x^2+5x-4) ----->
((2x^2-x)-(x^2+7x+12))/(2x^2+5x-4)

4. Subtract, then combine like terms

Final answer:
(x^2-8x-12)/(2x^2+5x-4)

User Jeffery
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