document.write( "Question 207386: factoring trinomials completely..........this is my problem and I can't figure out how to work any of them.....
\n" ); document.write( "36t^2+390t+64
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Algebra.Com's Answer #156814 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!

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\n" ); document.write( "\n" ); document.write( "\"36t%5E2%2B390t%2B64\" Start with the given expression.\r
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\n" ); document.write( "\n" ); document.write( "\"2%2818t%5E2%2B195t%2B32%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 \"18t%5E2%2B195t%2B32\"\r
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\n" ); document.write( "\n" ); document.write( "Looking at the expression \"18t%5E2%2B195t%2B32\", we can see that the first coefficient is \"18\", the second coefficient is \"195\", and the last term is \"32\".\r
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\n" ); document.write( "\n" ); document.write( "Now multiply the first coefficient \"18\" by the last term \"32\" to get \"%2818%29%2832%29=576\".\r
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\n" ); document.write( "\n" ); document.write( "Now the question is: what two whole numbers multiply to \"576\" (the previous product) and add to the second coefficient \"195\"?\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 \"576\" (the previous product).\r
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\n" ); document.write( "\n" ); document.write( "Factors of \"576\":\r
\n" ); document.write( "\n" ); document.write( "1,2,3,4,6,8,9,12,16,18,24,32,36,48,64,72,96,144,192,288,576\r
\n" ); document.write( "\n" ); document.write( "-1,-2,-3,-4,-6,-8,-9,-12,-16,-18,-24,-32,-36,-48,-64,-72,-96,-144,-192,-288,-576\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 \"576\".\r
\n" ); document.write( "\n" ); document.write( "1*576 = 576
\n" ); document.write( "2*288 = 576
\n" ); document.write( "3*192 = 576
\n" ); document.write( "4*144 = 576
\n" ); document.write( "6*96 = 576
\n" ); document.write( "8*72 = 576
\n" ); document.write( "9*64 = 576
\n" ); document.write( "12*48 = 576
\n" ); document.write( "16*36 = 576
\n" ); document.write( "18*32 = 576
\n" ); document.write( "24*24 = 576
\n" ); document.write( "(-1)*(-576) = 576
\n" ); document.write( "(-2)*(-288) = 576
\n" ); document.write( "(-3)*(-192) = 576
\n" ); document.write( "(-4)*(-144) = 576
\n" ); document.write( "(-6)*(-96) = 576
\n" ); document.write( "(-8)*(-72) = 576
\n" ); document.write( "(-9)*(-64) = 576
\n" ); document.write( "(-12)*(-48) = 576
\n" ); document.write( "(-16)*(-36) = 576
\n" ); document.write( "(-18)*(-32) = 576
\n" ); document.write( "(-24)*(-24) = 576\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 \"195\":\r
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First NumberSecond NumberSum
15761+576=577
22882+288=290
31923+192=195
41444+144=148
6966+96=102
8728+72=80
9649+64=73
124812+48=60
163616+36=52
183218+32=50
242424+24=48
-1-576-1+(-576)=-577
-2-288-2+(-288)=-290
-3-192-3+(-192)=-195
-4-144-4+(-144)=-148
-6-96-6+(-96)=-102
-8-72-8+(-72)=-80
-9-64-9+(-64)=-73
-12-48-12+(-48)=-60
-16-36-16+(-36)=-52
-18-32-18+(-32)=-50
-24-24-24+(-24)=-48
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\n" ); document.write( "\n" ); document.write( "From the table, we can see that the two numbers \"3\" and \"192\" add to \"195\" (the middle coefficient).\r
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\n" ); document.write( "\n" ); document.write( "So the two numbers \"3\" and \"192\" both multiply to \"576\" and add to \"195\"\r
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\n" ); document.write( "\n" ); document.write( "Now replace the middle term \"195t\" with \"3t%2B192t\". Remember, \"3\" and \"192\" add to \"195\". So this shows us that \"3t%2B192t=195t\".\r
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\n" ); document.write( "\n" ); document.write( "\"18t%5E2%2Bhighlight%283t%2B192t%29%2B32\" Replace the second term \"195t\" with \"3t%2B192t\".\r
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\n" ); document.write( "\n" ); document.write( "\"%2818t%5E2%2B3t%29%2B%28192t%2B32%29\" Group the terms into two pairs.\r
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\n" ); document.write( "\n" ); document.write( "\"3t%286t%2B1%29%2B%28192t%2B32%29\" Factor out the GCF \"3t\" from the first group.\r
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\n" ); document.write( "\n" ); document.write( "\"3t%286t%2B1%29%2B32%286t%2B1%29\" Factor out \"32\" from the second group. The goal of this step is to make the terms in the second parenthesis equal to the terms in the first parenthesis.\r
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\n" ); document.write( "\n" ); document.write( "\"%283t%2B32%29%286t%2B1%29\" Combine like terms. Or factor out the common term \"6t%2B1\"\r
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\n" ); document.write( "\n" ); document.write( "So \"2%2818t%5E2%2B195t%2B32%29\" then factors further to \"2%283t%2B32%29%286t%2B1%29\"\r
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\n" ); document.write( "\n" ); document.write( "Answer:\r
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\n" ); document.write( "\n" ); document.write( "So \"36t%5E2%2B390t%2B64\" completely factors to \"2%283t%2B32%29%286t%2B1%29\".\r
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\n" ); document.write( "\n" ); document.write( "In other words, \"36t%5E2%2B390t%2B64=2%283t%2B32%29%286t%2B1%29\".\r
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\n" ); document.write( "\n" ); document.write( "Note: you can check the answer by expanding \"2%283t%2B32%29%286t%2B1%29\" to get \"36t%5E2%2B390t%2B64\" or by graphing the original expression and the answer (the two graphs should be identical).\r
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