document.write( "Question 152616This question is from textbook Applied Calculus for the Managerial, Life and Social Sciences
\n" ); document.write( ": Use the quadratic formula to solve the following equation:\r
\n" ); document.write( "\n" ); document.write( "9x^2 - 12x = 4\r
\n" ); document.write( "\n" ); document.write( "The answer I worked was:
\n" ); document.write( "9x^2 - 12x - 4 = 0
\n" ); document.write( "x = -12 +/- sqrt 12^2 - 4(9)(4) / 2 (9)
\n" ); document.write( "x = 0/18
\n" ); document.write( "x = 0\r
\n" ); document.write( "\n" ); document.write( "However, in the book, it shows the answer as:
\n" ); document.write( "2/3(1 - sqrt 2); 2/3(1 + sqrt 2)\r
\n" ); document.write( "\n" ); document.write( "Can you please explain how I get to this answer? What am I doing wrong?\r
\n" ); document.write( "\n" ); document.write( "Thank you sooo much for your help.
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Algebra.Com's Answer #112179 by Edwin McCravy(20055)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "You don't have the formula right:\r\n" );
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document.write( "The solution to\r\n" );
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document.write( "\"ax%5E2%2Bbx%2Bc=0\"\r\n" );
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document.write( "is\r\n" );
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document.write( "\"x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+\"\r\n" );
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document.write( "Your problem is \r\n" );
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document.write( "\"9x%5E2+-+12x+-+4+=+0\"\r\n" );
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document.write( "\"a=9\", \"b=-12\", \"c=-4\"\r\n" );
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document.write( "\"x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+\"\r\n" );
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document.write( "\"x+=+%2812+%2B-+sqrt%28144%2B144%29%29%2F%282%2A%289%29%29+\"\r\n" );
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document.write( "\"x+=+%2812+%2B-+sqrt%28288%29%29%2F18+\"\r\n" );
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document.write( "\"x+=+%2812+%2B-+sqrt%28144%2A2%29%29%2F18+\"\r\n" );
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document.write( "\"x+=+%2812+%2B-+sqrt%28144%29sqrt%282%29%29%2F18+\"\r\n" );
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document.write( "\"x+=+%2812+%2B-+12sqrt%282%29%29%2F18+\"\r\n" );
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document.write( "Factor 12 out of the top\r\n" );
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document.write( "\"x+=+12%281+%2B-+sqrt%282%29%29%2F18+\"\r\n" );
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document.write( "Divide 12 and 18 by 6\r\n" );
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document.write( "\"x+=+2%281+%2B-+sqrt%282%29%29%2F3+\"\r\n" );
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document.write( "That is equivalent to your answers:\r\n" );
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document.write( "Edwin
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