document.write( "Question 191475: Factor the trinomial completely\r
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Algebra.Com's Answer #143675 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
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\n" ); document.write( "\n" ); document.write( "Looking at \"x%5E2y%5E2-6xy%2B9\" we can see that the first term is \"x%5E2y%5E2\" and the last term is \"9\" where the coefficients are 1 and 9 respectively.\r
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\n" ); document.write( "\n" ); document.write( "Now multiply the first coefficient 1 and the last coefficient 9 to get 9. Now what two numbers multiply to 9 and add to the middle coefficient -6? Let's list all of the factors of 9:\r
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\n" ); document.write( "\n" ); document.write( "Factors of 9:\r
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\n" ); document.write( "\n" ); document.write( "-1,-3 ...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 9\r
\n" ); document.write( "\n" ); document.write( "1*9\r
\n" ); document.write( "\n" ); document.write( "3*3\r
\n" ); document.write( "\n" ); document.write( "(-1)*(-9)\r
\n" ); document.write( "\n" ); document.write( "(-3)*(-3)\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 -6? Lets make a table of all of the pairs of factors we multiplied and see which two numbers add to -6\r
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First NumberSecond NumberSum
191+9=10
333+3=6
-1-9-1+(-9)=-10
-3-3-3+(-3)=-6
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\n" ); document.write( "\n" ); document.write( "From this list we can see that -3 and -3 add up to -6 and multiply to 9\r
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\n" ); document.write( "\n" ); document.write( "Now looking at the expression \"x%5E2y%5E2-6xy%2B9\", replace \"-6xy\" with \"-3xy-3xy\" (notice \"-3xy%2B-3xy\" adds up to \"-6xy\". So it is equivalent to \"-6xy\")\r
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\n" ); document.write( "\n" ); document.write( "\"x%5E2y%5E2%2Bhighlight%28-3xy-3xy%29%2B9\"\r
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\n" ); document.write( "\n" ); document.write( "Now let's factor \"x%5E2y%5E2-3xy-3xy%2B9\" by grouping:\r
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\n" ); document.write( "\n" ); document.write( "\"%28x%5E2y%5E2-3xy%29%2B%28-3xy%2B9%29\" Group like terms\r
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\n" ); document.write( "\n" ); document.write( "\"xy%28xy-3%29-3%28xy-3%29\" Factor out the GCF of \"xy\" out of the first group. Factor out the GCF of \"-3\" out of the second group\r
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\n" ); document.write( "\n" ); document.write( "\"%28xy-3%29%28xy-3%29\" Since we have a common term of \"xy-3\", we can combine like terms\r
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\n" ); document.write( "\n" ); document.write( "So \"x%5E2y%5E2-3xy-3xy%2B9\" factors to \"%28xy-3%29%28xy-3%29\"\r
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\n" ); document.write( "\n" ); document.write( "So this also means that \"x%5E2y%5E2-6xy%2B9\" factors to \"%28xy-3%29%28xy-3%29\" (since \"x%5E2y%5E2-6xy%2B9\" is equivalent to \"x%5E2y%5E2-3xy-3xy%2B9\")\r
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\n" ); document.write( "\n" ); document.write( "note: \"%28xy-3%29%28xy-3%29\" is equivalent to \"%28xy-3%29%5E2\" since the term \"xy-3\" occurs twice. So \"x%5E2y%5E2-6xy%2B9\" also factors to \"%28xy-3%29%5E2\"\r
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\n" ); document.write( "\n" ); document.write( " Answer:\r
\n" ); document.write( "\n" ); document.write( "So \"x%5E2y%5E2-6xy%2B9\" factors to \"%28xy-3%29%5E2\"
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