document.write( "Question 190285: Factor\r
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Algebra.Com's Answer #142806 by jim_thompson5910(35256)\"\" \"About 
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\n" ); document.write( "\n" ); document.write( "Looking at \"x%5E2%2B8xy%2B12y%5E2\" we can see that the first term is \"x%5E2\" and the last term is \"12y%5E2\" where the coefficients are 1 and 12 respectively.\r
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\n" ); document.write( "\n" ); document.write( "Now multiply the first coefficient 1 and the last coefficient 12 to get 12. Now what two numbers multiply to 12 and add to the middle coefficient 8? Let's list all of the factors of 12:\r
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\n" ); document.write( "\n" ); document.write( "Factors of 12:\r
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\n" ); document.write( "\n" ); document.write( "-1,-2,-3,-4,-6,-12 ...List the negative factors as well. 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 12\r
\n" ); document.write( "\n" ); document.write( "1*12\r
\n" ); document.write( "\n" ); document.write( "2*6\r
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\n" ); document.write( "\n" ); document.write( "(-1)*(-12)\r
\n" ); document.write( "\n" ); document.write( "(-2)*(-6)\r
\n" ); document.write( "\n" ); document.write( "(-3)*(-4)\r
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\n" ); document.write( "\n" ); document.write( "note: remember two negative numbers multiplied together make a positive number\r
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\n" ); document.write( "\n" ); document.write( "Now which of these pairs add to 8? Lets make a table of all of the pairs of factors we multiplied and see which two numbers add to 8\r
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First NumberSecond NumberSum
1121+12=13
262+6=8
343+4=7
-1-12-1+(-12)=-13
-2-6-2+(-6)=-8
-3-4-3+(-4)=-7
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\n" ); document.write( "\n" ); document.write( "From this list we can see that 2 and 6 add up to 8 and multiply to 12\r
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\n" ); document.write( "\n" ); document.write( "Now looking at the expression \"x%5E2%2B8xy%2B12y%5E2\", replace \"8xy\" with \"2xy%2B6xy\" (notice \"2xy%2B6xy\" adds up to \"8xy\". So it is equivalent to \"8xy\")\r
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\n" ); document.write( "\n" ); document.write( "\"x%5E2%2Bhighlight%282xy%2B6xy%29%2B12y%5E2\"\r
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\n" ); document.write( "\n" ); document.write( "Now let's factor \"x%5E2%2B2xy%2B6xy%2B12y%5E2\" by grouping:\r
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\n" ); document.write( "\n" ); document.write( "\"%28x%5E2%2B2xy%29%2B%286xy%2B12y%5E2%29\" Group like terms\r
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\n" ); document.write( "\n" ); document.write( "\"x%28x%2B2y%29%2B6y%28x%2B2y%29\" Factor out the GCF of \"x\" out of the first group. Factor out the GCF of \"6y\" out of the second group\r
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\n" ); document.write( "\n" ); document.write( "\"%28x%2B6y%29%28x%2B2y%29\" Since we have a common term of \"x%2B2y\", we can combine like terms\r
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\n" ); document.write( "\n" ); document.write( "So \"x%5E2%2B2xy%2B6xy%2B12y%5E2\" factors to \"%28x%2B6y%29%28x%2B2y%29\"\r
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\n" ); document.write( "\n" ); document.write( "So this also means that \"x%5E2%2B8xy%2B12y%5E2\" factors to \"%28x%2B6y%29%28x%2B2y%29\" (since \"x%5E2%2B8xy%2B12y%5E2\" is equivalent to \"x%5E2%2B2xy%2B6xy%2B12y%5E2\")\r
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\n" ); document.write( "\n" ); document.write( " Answer:\r
\n" ); document.write( "\n" ); document.write( "So \"x%5E2%2B8xy%2B12y%5E2\" factors to \"%28x%2B6y%29%28x%2B2y%29\"
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