document.write( "Question 93247: (x^2-9)/(2x-6) \n" ); document.write( "
Algebra.Com's Answer #67884 by bucky(2189)\"\" \"About 
You can put this solution on YOUR website!
Given:
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\n" ); document.write( "\"%28x%5E2-9%29%2F%282x-6%29\"
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\n" ); document.write( "Note that the numerator is the difference of two squares. As such it can be factored
\n" ); document.write( "using the following rule:
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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( "This form is identical to the numerator in the given expression if you let A = x and B = 3.
\n" ); document.write( "Substituting these into the rule you get:
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\n" ); document.write( "\"%28x%5E2+-+9%29+=+x%5E2+-+3%5E2+=+%28x-3%29%2A%28x%2B3%29\"
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\n" ); document.write( "So in place of \"x%5E2+-+9\" you can substitute \"%28x-3%29%2A%28x%2B3%29\" to convert the given
\n" ); document.write( "expression to:
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\n" ); document.write( "\"%28%28x-3%29%2A%28x%2B3%29%29%2F%282x-6%29\"
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\n" ); document.write( "Then notice that the denominator can be factored because 2 is common to both terms in
\n" ); document.write( "the denominator. When you factor the 2 you then have:
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\n" ); document.write( "\"%28%28x-3%29%2A%28x%2B3%29%29%2F%282%28x-3%29%29\"
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\n" ); document.write( "Then you can cancel the term in the denominator that is common with the one in the numerator
\n" ); document.write( "to get:
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\n" ); document.write( "\"%28%28cross%28x-3%29%29%2A%28x%2B3%29%29%2F%282%2A%28cross%28x-3%29%29%29\"
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\n" ); document.write( "and what remains is:
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\n" ); document.write( "\"%28x%2B3%29%2F2\"
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\n" ); document.write( "This is the answer to the problem.
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\n" ); document.write( "Hope this helps you to understand a method for reducing the problem to a lower form.
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