document.write( "Question 152454: factor by grouping:\r
\n" ); document.write( "\n" ); document.write( "8x^2+18x-35 \n" ); document.write( "
Algebra.Com's Answer #112091 by Edwin McCravy(20054)\"\" \"About 
You can put this solution on YOUR website!
factor by grouping: \r
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document.write( "Multiply the \"8\" by the \"-35\" and get \"-280\"\r\n" );
document.write( "Write down all the pairs of factors of its absolute value,\r\n" );
document.write( "\"280\":\r\n" );
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document.write( "\"280%2A1\"\r\n" );
document.write( "\"140%2A2\"\r\n" );
document.write( "\"70%2A4\"\r\n" );
document.write( "\"56%2A5\"\r\n" );
document.write( "\"40%2A7\"\r\n" );
document.write( "\"35%2A8\"\r\n" );
document.write( "\"28%2A10\"\r\n" );
document.write( "\"20%2A14\"\r\n" );
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document.write( "Now since the LAST SIGN in \"8x%5E2%2B18x-35\"\r\n" );
document.write( "is MINUS, we SUBTRACT the two \r\n" );
document.write( "factors in absolute value:\r\n" );
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document.write( "[Note: If the last term had been PLUS, we \r\n" );
document.write( "would have ADDED the two factors in \r\n" );
document.write( "absolute value.]\r\n" );
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document.write( "\"280-1=279\"\r\n" );
document.write( "\"140-2=138\"\r\n" );
document.write( "\"70-4-66\"\r\n" );
document.write( "\"56-5=51\"\r\n" );
document.write( "\"40-7=33\"\r\n" );
document.write( "\"35-8=27\"\r\n" );
document.write( "\"28-10=18\"\r\n" );
document.write( "\"20-14=6\"\r\n" );
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document.write( "Now we look at the middle term of \"8x%5E2%2B18x-35\",\r\n" );
document.write( "which is \"18\" and we look at the \r\n" );
document.write( "list of differences and find the\r\n" );
document.write( "absolute value of \"18\" in the next to\r\n" );
document.write( "last difference, \"28-10=18\".\r\n" );
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document.write( "So we substitute \"28-10\" for the 18:\r\n" );
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document.write( "\"8x%5E2%2B18x-35\"\r\n" );
document.write( "\"8x%5E2%2B%2828-10%29x-35\"\r\n" );
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document.write( "Now we remove the parentheses by distributing:\r\n" );
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document.write( "\"8x%5E2%2B28x-10x-35\"\r\n" );
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document.write( "Factor \"4x\" out of the first two terms\r\n" );
document.write( "Factor \"-5\" out of the last two terms:\r\n" );
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document.write( "\"4x%2A%282x%2B7%29-5%282x%2B7%29\"\r\n" );
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document.write( "Now factor out \"%282x%2B7%29\"\r\n" );
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document.write( "\"%282x%2B7%29%284x-5%29\"\r\n" );
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document.write( "Edwin
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