document.write( "Question 131900: I was doing fine on my homework in till I came to a couple of questions that I could not figure out, if you could help me I would really appreciate it.
\n" ); document.write( "Here is the problem 2x+6/x^2-9 + 1/x+3
\n" ); document.write( "I think that if I could find the LCD for the denominators then I could figure out the rest of the problem. I do know that the answers has to be one of these...
\n" ); document.write( "A) 3/x-3
\n" ); document.write( "B) 3(x+1)/(x+3)(x-3)
\n" ); document.write( "C) 3(x+1)/x(x-3)
\n" ); document.write( "D) 2/x-3
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Algebra.Com's Answer #96418 by bucky(2189)\"\" \"About 
You can put this solution on YOUR website!
Given to simplify:
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\n" ); document.write( "\"%282x%2B6%29%2F%28x%5E2+-+9%29+%2B+1%2F%28x%2B3%29\"
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\n" ); document.write( "The factor form you are looking for is:
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\n" ); document.write( "\"a%5E2+-+b%5E2+=+%28a-b%29%2A%28a%2Bb%29\"
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\n" ); document.write( "The way to look at this is if you have the difference between two perfect squares, it factors into
\n" ); document.write( "the product of the sum and the difference of the two square roots. Notice that \"x%5E2\" is a
\n" ); document.write( "perfect square and so is \"9\". So \"x%5E2+-+9\" factors into \"%28x-3%29%2A%28x%2B3%29\". This makes the
\n" ); document.write( "problem become:
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\n" ); document.write( "\"%282x%2B6%29%2F%28%28x-3%29%2A%28x%2B3%29%29+%2B+1%2F%28x%2B3%29\"
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\n" ); document.write( "You can now put the second fraction over a common denominator of \"%28x-3%29%2A%28x%2B3%29\" by
\n" ); document.write( "multiplying the second fraction by \"%28x-3%29%2F%28x-3%29\" to make the problem:
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\n" ); document.write( "and this makes the problem become:
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\n" ); document.write( "\"%282x%2B6%29%2F%28%28x-3%29%2A%28x%2B3%29%29+%2B+%28x-3%29%2F%28%28x-3%29%2A%28x%2B3%29%29\"
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\n" ); document.write( "Since the two fractions now have a common denominator, you can combine their two numerators over
\n" ); document.write( "the common denominator and you have:
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\n" ); document.write( "\"%282x+%2B+6+%2B+x+-+3%29%2F%28%28x-3%29%2A%28x%2B3%29%29\"
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\n" ); document.write( "In the numerator combine the 2x and + x to get 3x and also combine the +6 and -3 to get +3.
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\n" ); document.write( "This makes the fraction become:
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\n" ); document.write( "\"%283x+%2B+3%29%2F%28%28x+-3%29%2A%28x%2B3%29%29\"
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\n" ); document.write( "Notice that the numerator can be factored by taking out a 3 to get:
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\n" ); document.write( "\"%283%28x%2B1%29%29%2F%28%28x+-3%29%2A%28x%2B3%29%29\"
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\n" ); document.write( "This looks like answer B on your answer list.
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\n" ); document.write( "Hope this helps you to understand the problem and how to work it.
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