document.write( "Question 95951This question is from textbook Precalculus with limits
\n" ); document.write( ": Solve the equation: (7/(2x+1))-(8x/(2x-1))=-4
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Algebra.Com's Answer #69890 by bucky(2189)\"\" \"About 
You can put this solution on YOUR website!
Given to solve:
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\n" ); document.write( "\"%287%2F%282x%2B1%29%29-%288x%2F%282x-1%29%29=-4\"
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\n" ); document.write( "If you don't like fractions, in this case you can get rid of the fractions. How? Begin by noting
\n" ); document.write( "that \"%282x%2B1%29%282x-1%29\" is a common denominator. Suppose that we multiply both sides of this
\n" ); document.write( "equation (all terms) by \"%282x%2B1%29%282x-1%29\". In doing that multiplication you make the original
\n" ); document.write( "problem become:
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\n" ); document.write( "Next, where it applies you can cancel the denominator with the like term in the numerator as
\n" ); document.write( "follows:
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\n" ); document.write( "After these cancellations you are left with:
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\n" ); document.write( "\"%28%282x+-1%29%2A7%29+-+%28%282x%2B1%29%2A8x%29+=+-4%2A%282x%2B1%29%282x-1%29\"
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\n" ); document.write( "Multiplying \"%282x+-+1%29%2A7\" results in \"14x+-+7\"
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\n" ); document.write( "Multiplying \"%282x+%2B+1%29%2A8x\" results in \"16x%5E2+%2B+8x\"
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\n" ); document.write( "and finally,
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\n" ); document.write( "Multiplying \"-4%2A%282x%2B1%29%282x+-1%29\" results in \"-16x%5E2+%2B+4\"
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\n" ); document.write( "Substitute these results into the equation and you have:
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\n" ); document.write( "\"14x+-+7+-+%2816x%5E2+%2B+8x%29+=+-16x%5E2+%2B+4\"
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\n" ); document.write( "On the left side you can remove the parentheses if you change the signs of the terms inside
\n" ); document.write( "the parentheses to get:
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\n" ); document.write( "\"14x+-+7+-+16x%5E2+-+8x+=+-16x%5E2+%2B+4\"
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\n" ); document.write( "Notice that you have \"-16x%5E2\" on both sides. Therefore, if you add \"16x%5E2\" to
\n" ); document.write( "both sides these two terms disappear and you are left with:
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\n" ); document.write( "\"14x+-+7+-+8x+=+4\"
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\n" ); document.write( "On the left side you can combine the \"14x\" and the \"-8x\" to get \"6x\" to reduce
\n" ); document.write( "the equation to:
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\n" ); document.write( "\"6x+-+7+=+4\"
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\n" ); document.write( "Then get rid of the -7 on the left side by adding 7 to both sides to get:
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\n" ); document.write( "\"6x+=+11\"
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\n" ); document.write( "Finally, solve for x by dividing both sides by 6 to get:
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\n" ); document.write( "\"x+=+11%2F6\"
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\n" ); document.write( "This is the answer you are looking for ... \"x+=+11%2F6\"
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\n" ); document.write( "You can check this answer by substituting \"11%2F6\" for x in the original problem and
\n" ); document.write( "ensuring that the equation will balance.
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\n" ); document.write( "Hope this helps you to understand the problem and how you can get rid of the denominators in
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