document.write( "Question 74127: x+5/x-5+3/x+5 \n" ); document.write( "
Algebra.Com's Answer #53190 by bucky(2189)\"\" \"About 
You can put this solution on YOUR website!
\"x%2B5%2Fx-5%2B3%2Fx%2B5\"
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\n" ); document.write( "Because you didn't use parentheses, the rules of math say that your problem should be interpreted
\n" ); document.write( "as above.
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\n" ); document.write( "In simplifying that problem, note that the +5 and the -5 cancel each other. Then the two terms
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\n" ); document.write( "\"5%2Fx\" and \"3%2Fx\" can be added to \"8%2Fx\" and these to operations reduce your problem
\n" ); document.write( "to:
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\n" ); document.write( "\"x+%2B+%288%2Fx%29\"
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\n" ); document.write( "This can be further simplified by getting the two terms to have a common denominator of
\n" ); document.write( "x. Do this by multiplying the x by \"x%2Fx\" which is equivalent to multiplying the x by 1
\n" ); document.write( "since \"x%2Fx\" is equivalent to 1
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\n" ); document.write( "The expression is then:
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\n" ); document.write( "\"%28x%5E2%2Fx%29+%2B+%288%2Fx%29+=+%28x%5E2+%2B+8%29%2Fx%29\"
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\n" ); document.write( "and that's the simplification of the expression the way you wrote it. If you had used
\n" ); document.write( "parentheses to lump things together, I think you meant to write:
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\n" ); document.write( "(x+5)/(x-5) - (3/(x+5))
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\n" ); document.write( "And that would translate to:
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\n" ); document.write( "\"%28%28x%2B5%29%2F%28x-5%29%29+-+%283%2F%28x%2B5%29%29\"
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\n" ); document.write( "And as you can see, that's a whole different problem. Parentheses are very important if you
\n" ); document.write( "are trying to communicate what you really mean.
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\n" ); document.write( "To solve this problem, we again need to get a common denominator. That denominator is
\n" ); document.write( "(x-5)*(x+5).
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\n" ); document.write( "To get the first term over the common denominator multiply it by \"%28x%2B5%29%2F%28x%2B5%29\".
\n" ); document.write( "This multiplication is:
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\n" ); document.write( "And if you square the numerator it becomes :
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\n" ); document.write( "\"%28x%5E2+%2B+10x+%2B+25%29%2F%28%28x-5%29%2A%28x%2B5%29%29\"
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\n" ); document.write( "That takes care of the first part of the problem. The second part consists of placing the second
\n" ); document.write( "term over the common denominator also. Recall that the second term was:
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\n" ); document.write( "\"-+%283%2F%28x%2B5%29%29\"
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\n" ); document.write( "Put it over the common denominator by multiplying it by \"%28x-5%29%2F%28x-5%29\". This multiplication
\n" ); document.write( "results in:
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\n" ); document.write( "Now we can get the total answer because the two terms are over a common denominator.
\n" ); document.write( "Because of that we can add the numerators of the two terms and place the sum over the
\n" ); document.write( "common denominator. The first term plus the second term is:
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\n" ); document.write( "The numerator of the combination becomes:
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\n" ); document.write( "\"x%5E2+%2B+10x+%2B+25+-+3x+%2B+15\"
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\n" ); document.write( "And this simplifies to \"x%5E2+%2B+7x+%2B+40\". Putting this over the common denominator
\n" ); document.write( "makes the answer:
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\n" ); document.write( "\"%28x%5E2+%2B+7x+%2B+40%29%2F%28%28x-5%29%2A%28x%2B5%29%29\"
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\n" ); document.write( "And if you multiply out the common denominator, the result is:
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\n" ); document.write( "\n" ); document.write( "\"%28x%5E2+%2B+7x+%2B+40%29%2F%28x%5E2+-+25%29\"
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\n" ); document.write( "I hope this impresses you with the difference in the two interpretations of the problem you
\n" ); document.write( "presented. The use of parentheses make these two answers completely different and shows
\n" ); document.write( "why it's so important to group terms to say what you really mean.\r
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