document.write( "Question 187134: please factor out this polynomial.
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\n" ); document.write( "4x+12xy+9y^2
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Algebra.Com's Answer #140274 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
I'm assuming that the expression is really \"4x%5E2%2B12xy%2B9y%5E2\". If not, then let me know.\r
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\n" ); document.write( "\n" ); document.write( "Looking at \"4x%5E2%2B12xy%2B9y%5E2\" we can see that the first term is \"4x%5E2\" and the last term is \"9y%5E2\" where the coefficients are 4 and 9 respectively.\r
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\n" ); document.write( "\n" ); document.write( "Now multiply the first coefficient 4 and the last coefficient 9 to get 36. Now what two numbers multiply to 36 and add to the middle coefficient 12? Let's list all of the factors of 36:\r
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\n" ); document.write( "\n" ); document.write( "Factors of 36:\r
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\n" ); document.write( "\n" ); document.write( "-1,-2,-3,-4,-6,-9,-12,-18 ...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 36\r
\n" ); document.write( "\n" ); document.write( "1*36\r
\n" ); document.write( "\n" ); document.write( "2*18\r
\n" ); document.write( "\n" ); document.write( "3*12\r
\n" ); document.write( "\n" ); document.write( "4*9\r
\n" ); document.write( "\n" ); document.write( "6*6\r
\n" ); document.write( "\n" ); document.write( "(-1)*(-36)\r
\n" ); document.write( "\n" ); document.write( "(-2)*(-18)\r
\n" ); document.write( "\n" ); document.write( "(-3)*(-12)\r
\n" ); document.write( "\n" ); document.write( "(-4)*(-9)\r
\n" ); document.write( "\n" ); document.write( "(-6)*(-6)\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 12? Lets make a table of all of the pairs of factors we multiplied and see which two numbers add to 12\r
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First NumberSecond NumberSum
1361+36=37
2182+18=20
3123+12=15
494+9=13
666+6=12
-1-36-1+(-36)=-37
-2-18-2+(-18)=-20
-3-12-3+(-12)=-15
-4-9-4+(-9)=-13
-6-6-6+(-6)=-12
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\n" ); document.write( "\n" ); document.write( "From this list we can see that 6 and 6 add up to 12 and multiply to 36\r
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\n" ); document.write( "\n" ); document.write( "Now looking at the expression \"4x%5E2%2B12xy%2B9y%5E2\", replace \"12xy\" with \"6xy%2B6xy\" (notice \"6xy%2B6xy\" adds up to \"12xy\". So it is equivalent to \"12xy\")\r
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\n" ); document.write( "\n" ); document.write( "\"4x%5E2%2Bhighlight%286xy%2B6xy%29%2B9y%5E2\"\r
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\n" ); document.write( "\n" ); document.write( "Now let's factor \"4x%5E2%2B6xy%2B6xy%2B9y%5E2\" by grouping:\r
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\n" ); document.write( "\n" ); document.write( "\"%284x%5E2%2B6xy%29%2B%286xy%2B9y%5E2%29\" Group like terms\r
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\n" ); document.write( "\n" ); document.write( "\"2x%282x%2B3y%29%2B3y%282x%2B3y%29\" Factor out the GCF of \"2x\" out of the first group. Factor out the GCF of \"3y\" out of the second group\r
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\n" ); document.write( "\n" ); document.write( "\"%282x%2B3y%29%282x%2B3y%29\" Since we have a common term of \"2x%2B3y\", we can combine like terms\r
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\n" ); document.write( "\n" ); document.write( "So \"4x%5E2%2B6xy%2B6xy%2B9y%5E2\" factors to \"%282x%2B3y%29%282x%2B3y%29\"\r
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\n" ); document.write( "\n" ); document.write( "So this also means that \"4x%5E2%2B12xy%2B9y%5E2\" factors to \"%282x%2B3y%29%282x%2B3y%29\" (since \"4x%5E2%2B12xy%2B9y%5E2\" is equivalent to \"4x%5E2%2B6xy%2B6xy%2B9y%5E2\")\r
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\n" ); document.write( "\n" ); document.write( "note: \"%282x%2B3y%29%282x%2B3y%29\" is equivalent to \"%282x%2B3y%29%5E2\" since the term \"2x%2B3y\" occurs twice. So \"4x%5E2%2B12xy%2B9y%5E2\" also factors to \"%282x%2B3y%29%5E2\"\r
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\n" ); document.write( "\n" ); document.write( " Answer:\r
\n" ); document.write( "\n" ); document.write( "So \"4x%5E2%2B12xy%2B9y%5E2\" factors to \"%282x%2B3y%29%5E2\"
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