document.write( "Question 167537: please help me solve these problems! Thanks!\r
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Algebra.Com's Answer #123461 by Edwin McCravy(20055)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "\"x%5E3-3x2-x%2B3=0\"\r\n" );
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document.write( "Factor just the first two terms:\r\n" );
document.write( "         \"x%5E3-3x%5E2\" \r\n" );
document.write( "         factor out \"x%5E2\" \r\n" );
document.write( "         \"x%5E2%28x-3%29\"\r\n" );
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document.write( "Factor just the last two terms\r\n" );
document.write( "         (((-x+3}}}  \r\n" );
document.write( "         factor out \"-1\"\r\n" );
document.write( "         \"-1%28x-3%29\"\r\n" );
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document.write( "Substitute \"x%5E2%28x-3%29\" for the\r\n" );
document.write( "first two terms and \"-1%28x-3%29\"\r\n" );
document.write( "for the last two terms in\r\n" );
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document.write( "\"x%5E3-3x2-x%2B3=0\"\r\n" );
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document.write( "\"x%5E2%28x-3%29-1%28x-3%29=0\"\r\n" );
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document.write( "Now factor the whole parentheses \"%28x-3%29\"\r\n" );
document.write( "out of both:\r\n" );
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document.write( "\"%28x-3%29%28x%5E2-1%29=0\"\r\n" );
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document.write( "The binomial in the second parentheses is the \r\n" );
document.write( "difference or two squares, as you see:\r\n" );
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document.write( "\"%28x-3%29%28x%5E2-1%5E2%29=0\"\r\n" );
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document.write( "So it factors as \"%28x-1%29%28x%2B1%29\":\r\n" );
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document.write( "\"%28x-3%29%28x-1%29%28x%2B1%29=0\"\r\n" );
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document.write( "Use the zero-factor principle:\r\n" );
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document.write( "\"y%5E2%2B2y-21=-2y\"\r\n" );
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document.write( "Get \"0\" on the right by adding \"2y\" to both sides of:\r\n" );
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document.write( "\"y%5E2%2B2y-21=-2y\"\r\n" );
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document.write( "\"y%5E2%2B4y-21=0\"\r\n" );
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document.write( "Think of two whole numbers which when multiplied gives \"-21\"\r\n" );
document.write( "and when added gives \"matrix%281%2C2%2C%22%2B%22%2C4%29\".  They are \"matrix%281%2C2%2C%22%2B%22%2C7%29\"\r\n" );
document.write( "and \"-3\".  So the left side factors as\r\n" );
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document.write( "\"%28y%2B7%29%28y-3%29=0\"\r\n" );
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document.write( "Use the zero-factor principle:\r\n" );
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document.write( "\"matrix%282%2C3%2C+y%2B7=0%2C+%22%7C%22%2C+y-3=0%2C+y=-7%2C++%22%7C%22%2C++y=3%29\"  \r\n" );
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document.write( "Edwin
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