document.write( "Question 167732: Factorize\r
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Algebra.Com's Answer #123640 by jim_thompson5910(35256)\"\" \"About 
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\n" ); document.write( "\n" ); document.write( "\"a%283x%5E2%2B7x%2B2%29\" Factor out the GCF \"a\"\r
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\n" ); document.write( "\n" ); document.write( "Now let's focus on the inner expression \"3x%5E2%2B7x%2B2\"\r
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\n" ); document.write( "\n" ); document.write( "Looking at \"3x%5E2%2B7x%2B2\" we can see that the first term is \"3x%5E2\" and the last term is \"2\" where the coefficients are 3 and 2 respectively.\r
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\n" ); document.write( "\n" ); document.write( "Now multiply the first coefficient 3 and the last coefficient 2 to get 6. Now what two numbers multiply to 6 and add to the middle coefficient 7? Let's list all of the factors of 6:\r
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\n" ); document.write( "\n" ); document.write( "Factors of 6:\r
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\n" ); document.write( "\n" ); document.write( "-1,-2,-3,-6 ...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 6\r
\n" ); document.write( "\n" ); document.write( "1*6\r
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\n" ); document.write( "\n" ); document.write( "(-1)*(-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 7? Lets make a table of all of the pairs of factors we multiplied and see which two numbers add to 7\r
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First NumberSecond NumberSum
161+6=7
232+3=5
-1-6-1+(-6)=-7
-2-3-2+(-3)=-5
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\n" ); document.write( "\n" ); document.write( "From this list we can see that 1 and 6 add up to 7 and multiply to 6\r
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\n" ); document.write( "\n" ); document.write( "Now looking at the expression \"3x%5E2%2B7x%2B2\", replace \"7x\" with \"1x%2B6x\" (notice \"1x%2B6x\" adds up to \"7x\". So it is equivalent to \"7x\")\r
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\n" ); document.write( "\n" ); document.write( "\"3x%5E2%2Bhighlight%281x%2B6x%29%2B2\"\r
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\n" ); document.write( "\n" ); document.write( "Now let's factor \"3x%5E2%2B1x%2B6x%2B2\" by grouping:\r
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\n" ); document.write( "\n" ); document.write( "\"%283x%5E2%2B1x%29%2B%286x%2B2%29\" Group like terms\r
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\n" ); document.write( "\n" ); document.write( "\"x%283x%2B1%29%2B2%283x%2B1%29\" Factor out the GCF of \"x\" out of the first group. Factor out the GCF of \"2\" out of the second group\r
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\n" ); document.write( "\n" ); document.write( "\"%28x%2B2%29%283x%2B1%29\" Since we have a common term of \"3x%2B1\", we can combine like terms\r
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\n" ); document.write( "\n" ); document.write( "So \"3x%5E2%2B1x%2B6x%2B2\" factors to \"%28x%2B2%29%283x%2B1%29\"\r
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\n" ); document.write( "\n" ); document.write( "So this also means that \"3x%5E2%2B7x%2B2\" factors to \"%28x%2B2%29%283x%2B1%29\" (since \"3x%5E2%2B7x%2B2\" is equivalent to \"3x%5E2%2B1x%2B6x%2B2\")\r
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\n" ); document.write( "\n" ); document.write( "So our expression goes from \"a%283x%5E2%2B7x%2B2%29\" and factors further to \"a%28x%2B2%29%283x%2B1%29\"\r
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\n" ); document.write( "\n" ); document.write( "So \"3ax%5E2%2B7ax%2B2a\" factors to \"a%28x%2B2%29%283x%2B1%29\"\r
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