document.write( "Question 892659: factor completely\r
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Algebra.Com's Answer #540683 by jim_thompson5910(35256)\"\" \"About 
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\n" ); document.write( "\n" ); document.write( "\"2x%5E2-24x-14\" Start with the given expression.\r
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\n" ); document.write( "\n" ); document.write( "\"2%28x%5E2-12x-7%29\" Factor out the GCF \"2\".\r
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\n" ); document.write( "\n" ); document.write( "Now let's try to factor the inner expression \"x%5E2-12x-7\"\r
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\n" ); document.write( "\n" ); document.write( "Looking at the expression \"x%5E2-12x-7\", we can see that the first coefficient is \"1\", the second coefficient is \"-12\", and the last term is \"-7\".\r
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\n" ); document.write( "\n" ); document.write( "Now multiply the first coefficient \"1\" by the last term \"-7\" to get \"%281%29%28-7%29=-7\".\r
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\n" ); document.write( "\n" ); document.write( "Now the question is: what two whole numbers multiply to \"-7\" (the previous product) and add to the second coefficient \"-12\"?\r
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\n" ); document.write( "\n" ); document.write( "To find these two numbers, we need to list all of the factors of \"-7\" (the previous product).\r
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\n" ); document.write( "\n" ); document.write( "Factors of \"-7\":\r
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\n" ); document.write( "\n" ); document.write( "Note: list the negative of each factor. This will allow us to find all possible combinations.\r
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\n" ); document.write( "\n" ); document.write( "These factors pair up and multiply to \"-7\".\r
\n" ); document.write( "\n" ); document.write( "1*(-7) = -7
\n" ); document.write( "(-1)*(7) = -7\r
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\n" ); document.write( "\n" ); document.write( "Now let's add up each pair of factors to see if one pair adds to the middle coefficient \"-12\":\r
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First NumberSecond NumberSum
1-71+(-7)=-6
-17-1+7=6
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\n" ); document.write( "\n" ); document.write( "From the table, we can see that there are no pairs of numbers which add to \"-12\". So \"x%5E2-12x-7\" cannot be factored.\r
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\n" ); document.write( "\n" ); document.write( "Answer:\r
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\n" ); document.write( "\n" ); document.write( "So \"2x%5E2-24x-14\" simply factors to \"2%28x%5E2-12x-7%29\"\r
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\n" ); document.write( "\n" ); document.write( "In other words, \"2x%5E2-24x-14=2%28x%5E2-12x-7%29\".
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