document.write( "Question 1172888: Solve the equation by factoring.\r
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Algebra.Com's Answer #798044 by ikleyn(52776) $\"\"$ $\"About$

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document.write( "Introduce new variable  u = 5x.\r\n" );
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document.write( "Then the equation takes the form\r\n" );
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document.write( "    u^2 + 6u + 8 = 0.\r\n" );
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document.write( "Factor it mentally in 1 second\r\n" );
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document.write( "    (u + 4)*(u + 2) = 0\r\n" );
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document.write( "The roots are  u= -4  and  u= -2.\r\n" );
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document.write( "Hence, the roots of the original equations are\r\n" );
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document.write( "    a)  5x = -4,  x = ,\r\n" );
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document.write( "and\r\n" );
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document.write( "    b)  5x = -2,  x = .\r\n" );
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