document.write( "Question 86530: divide\r
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Algebra.Com's Answer #62747 by bucky(2189)\"\" \"About 
You can put this solution on YOUR website!
Given:
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\n" ); document.write( "\"%282x+-+6%29%2F21\"
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\n" ); document.write( "Divide it by:
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\n" ); document.write( "\"%285x+-+15%29%2F12\"
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\n" ); document.write( "Recall the \"arithmetic\" rule about fractions. If you are dividing by a fraction you can
\n" ); document.write( "invert the divisor and multiply it by the dividend. In this case it means you can take
\n" ); document.write( "\"%282x+-+6%29%2F21\" and multiply it by the inversion of \"%285x+-+15%29%2F12\" to get the answer
\n" ); document.write( "to this problem. After the inversion, the original division problem is converted to the
\n" ); document.write( "following multiplication problem:
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\n" ); document.write( "\"%28%282x+-+6%29%2F21%29%2A%2812%2F%285x-15%29%29\"
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\n" ); document.write( "Before it gets too complicated, let's do some factoring. Note that:
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\n" ); document.write( "\"2x+-+6\" factors to \"2%2A%28x+-+3%29\" and
\n" ); document.write( "\"+21\" factors to \"7%2A3\" and
\n" ); document.write( "\"12\" factors to \"4%2A3\" and
\n" ); document.write( "\"5x+-+15\" factors to \"5%2A%28x-3%29\"
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\n" ); document.write( "Substitute all these factored forms into the appropriate places in the multiplication
\n" ); document.write( "problem and it becomes:
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\n" ); document.write( "\"%28%282%2A%28x-3%29%29%2F%287%2A3%29%29%2A%28%284%2A3%29%2F%285%2A%28x-3%29%29%29\"
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\n" ); document.write( "Cancel all the terms that appear in the numerator with a corresponding appearance in
\n" ); document.write( "the denominator as follows:
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\n" ); document.write( "The remaining factors in the numerator are 4 and 2. They multiply out to 8. And the remaining
\n" ); document.write( "factors in the denominator are 7 and 5 and they multiply out to 35. This makes the answer:
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\n" ); document.write( "\"8%2F35\" and there are no more common factors in the numerator and the denominator.
\n" ); document.write( "So this cannot be reduced further and the answer to the original problem is \"8%2F35\"
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\n" ); document.write( "Hope this helps you to understand the division process in this problem.
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