document.write( "Question 86680: add or subtract as indicated. x/x+4-36/x^2-x-20 \n" ); document.write( "
Algebra.Com's Answer #62746 by bucky(2189)\"\" \"About 
You can put this solution on YOUR website!
Given:
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\n" ); document.write( "\"%28x%2F%28x%2B4%29%29-%2836%2F%28x%5E2-x-20%29%29\"
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\n" ); document.write( "Notice first that \"x%5E2-x-20\" factors into \"%28x+%2B4%29%2A%28x+-5%29\". Substitute the factored
\n" ); document.write( "form into the problem, and the problem becomes:
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\n" ); document.write( "\"%28x%2F%28x%2B4%29%29-%2836%2F%28%28x%2B4%29%2A%28x-5%29%29%29%29\"
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\n" ); document.write( "Next, create a common denominator in the two terms by multiplying the first term by
\n" ); document.write( "\"%28x-5%29%2F%28x-5%29\" which is equivalent to multiplying by 1 because the numerator of this
\n" ); document.write( "multiplier is the same as the denominator. This multiplication makes the problem
\n" ); document.write( "become:
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\n" ); document.write( "and this simplifies to:
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\n" ); document.write( "The numerator of the first term multiplies out to \"x%5E2-5x\". Substituting this into
\n" ); document.write( "the polynomial makes it become:
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\n" ); document.write( "Now since the two terms have the same denominator, they can be combined by just subtracting
\n" ); document.write( "the two numerators and putting that result over the common denominator. This results
\n" ); document.write( "in:
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\n" ); document.write( "\"%28%28x%5E2+-+5x+-36%29%2F%28%28x%2B4%29%2A%28x-5%29%29%29%29\"
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\n" ); document.write( "Now notice that the numerator \"x%5E2+-+5x+-+36\" factors into \"%28x+-+9%29%2A%28x+%2B+4%29\".
\n" ); document.write( "Substitute this for the numerator and the result is:
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\n" ); document.write( "\"%28%28%28x-9%29%2A%28x%2B4%29%29%29%2F%28%28x%2B4%29%2A%28x-5%29%29%29%29\"
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\n" ); document.write( "Cancel the like terms in the numerator and denominator:
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\n" ); document.write( "and this reduces to the form:
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\n" ); document.write( "\"%28x-9%29%2F%28x-5%29\"
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\n" ); document.write( "This is the answer you are looking for. Hope this helps you to understand the problem
\n" ); document.write( "and how to work it through to an answer.
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