document.write( "Question 512996: Use polynomial long division to divide
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Algebra.Com's Answer #342835 by Edwin McCravy(20055) $\"\"$ $\"About$
You can put this solution on YOUR website!
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document.write( "-x² – x – 5)4x³ + x² + 17x – 15\r\n" );
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document.write( "We divide the 4x³ by -x²:   = -4x, so we put that\r\n" );
document.write( "above the 17x like this:\r\n" );
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document.write( "                       -4x        \r\n" );
document.write( "-x² – x – 5)4x³ + x² + 17x – 15\r\n" );
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document.write( "Then we multiply -4x by -x² - x - 5:  -4x(-x² - x - 5) = 4x³ + 4x² + 20x\r\n" );
document.write( "and write that down below \r\n" );
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document.write( "                        -4x       \r\n" );
document.write( "-x² – x – 5)4x³ +  x² + 17x – 15\r\n" );
document.write( "            4x³ + 4x² + 20x\r\n" );
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document.write( "Next we draw a line under that \r\n" );
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document.write( "                        -4x     \r\n" );
document.write( "-x² – x – 5)4x³ +  x² + 17x – 15\r\n" );
document.write( "            4x³ + 4x² + 20x\r\n" );
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document.write( "Now we subtract, imagining all the signs changed like this\r\n" );
document.write( "and adding:                \r\n" );
document.write( "                                4x³ +  x² + 17x \r\n" );
document.write( "                               -4x³ - 4x² - 20x\r\n" );
document.write( "                                     -3x² -  3x \r\n" );
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document.write( "We write that down under the line:\r\n" );
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document.write( "                       -4x                                \r\n" );
document.write( "-x² – x – 5)4x³ +  x² + 17x – 15\r\n" );
document.write( "            4x³ + 4x² + 20x\r\n" );
document.write( "                 -3x² -  3x\r\n" );
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document.write( "We bring down the -15\r\n" );
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document.write( "                       -4x       \r\n" );
document.write( "-x² – x – 5)4x³ +  x² + 17x – 15\r\n" );
document.write( "            4x³ + 4x² + 20x\r\n" );
document.write( "                 -3x² -  3x - 15\r\n" );
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document.write( "We divide the -3x² by -x²:   = +3, so we put that\r\n" );
document.write( "above the -15 like this (don't forget the + sign:\r\n" );
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document.write( "                       -4x  +  3 \r\n" );
document.write( "-x² – x – 5)4x³ +  x² + 17x – 15\r\n" );
document.write( "            4x³ + 4x² + 20x\r\n" );
document.write( "                 -3x² -  3x - 15\r\n" );
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document.write( "Then we multiply +3 by -x² - x - 5:  +3(-x²-x-5) = -3x² - 3x - 15\r\n" );
document.write( "and write that down below\r\n" );
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document.write( "                       -4x  +  3  \r\n" );
document.write( "-x² – x – 5)4x³ +  x² + 17x – 15\r\n" );
document.write( "            4x³ + 4x² + 20x\r\n" );
document.write( "                 -3x² -  3x - 15\r\n" );
document.write( "                 -3x² -  3x - 15\r\n" );
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document.write( "Next we draw a line under that \r\n" );
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document.write( "                       -4x  +  3  \r\n" );
document.write( "-x² – x – 5)4x³ +  x² + 17x – 15\r\n" );
document.write( "            4x³ + 4x² + 20x\r\n" );
document.write( "                 -3x² -  3x - 15\r\n" );
document.write( "                 -3x² -  3x - 15\r\n" );
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document.write( "Now we subtract, imagining all the signs changed like this\r\n" );
document.write( "and adding:                \r\n" );
document.write( "                               -3x² -  3x - 15 \r\n" );
document.write( "                                3x² +  3x + 15\r\n" );
document.write( "                                             0\r\n" );
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document.write( "And we get a 0 remainder, so the answer is the quotient -4x + 3\r\n" );
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document.write( "Edwin
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