document.write( "Question 128546: 1-3x
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\n" ); document.write( "\n" ); document.write( "can you show me how to simplify
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Algebra.Com's Answer #94056 by bucky(2189)\"\" \"About 
You can put this solution on YOUR website!
Given to simplify:
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\n" ); document.write( "\"%281-3x%29%2F%283x%5E2%2B14x-5%29\"
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\n" ); document.write( "Since these are \"setup\" problems that are designed to teach a point, you can make a guess
\n" ); document.write( "that the numerator and the denominator have a common term that cancels out.
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\n" ); document.write( "Let's re-write the numerator that it is arranged in descending powers of x ... that is
\n" ); document.write( "so the x term appears first followed by the constant. When we do that the problem becomes:
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\n" ); document.write( "\"%28-3x%2B1%29%2F%283x%5E2%2B14x-5%29\"
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\n" ); document.write( "Then in the numerator, factor out \"-1\" so that we make the \"3x\" term positive. This makes the
\n" ); document.write( "expression become:
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\n" ); document.write( "\"%28-1%29%283x-1%29%2F%283x%5E2%2B14x-5%29\"
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\n" ); document.write( "Now let's see if we can factor the denominator. And let's guess that one of the factors
\n" ); document.write( "might be \"3x-1%29\". This being the case we might begin the factoring with:
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\n" ); document.write( "\"%283x+-1%29%2A%28Ax+%2B+B%29\"
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\n" ); document.write( "We know that \"3x\" times \"Ax\" has to equal the \"3x%5E2\" of the given denominator. Therefore,
\n" ); document.write( "\"A\" will have to equal \"1\" so that \"3x%2A1x+=+3x%5E2\". So go to our factored form of the denominator
\n" ); document.write( "and substitute \"1\" for \"A\" to make the factored form:
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\n" ); document.write( "\"%283x-1%29%2A%281x+%2B+B%29\"
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\n" ); document.write( "Note that when we do the next step we just write the \"1x\" as \"x\"
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\n" ); document.write( "Next from this factored form we can see that if we multiply the constant \"-1\" by
\n" ); document.write( "B, it has to result in the \"-5\" of the original denominator of the problem. So we can
\n" ); document.write( "say that:
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\n" ); document.write( "\"%28-1%29%2AB+=+-5\"
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\n" ); document.write( "and we can solve this for B by multiplying both sides by \"-1\" to get:
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\n" ); document.write( "\"B+=+5\"
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\n" ); document.write( "Substitute this value for B in the factored form of our denominator and you have that the
\n" ); document.write( "factored form is:
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\n" ); document.write( "\"%283x-1%29%2A%28x+%2B+5%29\"
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\n" ); document.write( "You can check this out by doing the multiplication just to be sure that the product is
\n" ); document.write( "equal to the original denominator.
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\n" ); document.write( "Substitute this into the problem where we had rearranged the numerator and we now have:
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\n" ); document.write( "\"%28-1%29%283x-1%29%2F%28%283x-1%29%2A%28x%2B5%29%29\"
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\n" ); document.write( "Cancel the common factor in the numerator with the same factor in the denominator:
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\n" ); document.write( "\"%28-1%29%2A%28cross%283x-1%29%29%2F%28%28cross%283x-1%29%29%2A%28x%2B5%29%29\"
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\n" ); document.write( "And you are left with the simplified form:
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\n" ); document.write( "\"-1%2F%28x%2B5%29\"
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\n" ); document.write( "and that's your answer.
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\n" ); document.write( "Hope this explanation helps you to understand the problem.
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