document.write( "Question 151911: Using the quadratic formula, solve the following equation for X.
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Algebra.Com's Answer #111686 by jim_thompson5910(35256)\"\" \"About 
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\n" ); document.write( "\n" ); document.write( "\"3x%5E2%2B9x=-4\" Start with the given equation.\r
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\n" ); document.write( "\n" ); document.write( "\"3x%5E2%2B9x%2B4=0\" Add 4 to both sides.\r
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\n" ); document.write( "\n" ); document.write( "Notice we have a quadratic equation in the form of \"ax%5E2%2Bbx%2Bc\" where \"a=3\", \"b=9\", and \"c=4\"\r
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\n" ); document.write( "\n" ); document.write( "Let's use the quadratic formula to solve for x\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-b+%2B-+sqrt%28+b%5E2-4ac+%29%29%2F%282a%29\" Start with the quadratic formula\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-%289%29+%2B-+sqrt%28+%289%29%5E2-4%283%29%284%29+%29%29%2F%282%283%29%29\" Plug in \"a=3\", \"b=9\", and \"c=4\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-9+%2B-+sqrt%28+81-4%283%29%284%29+%29%29%2F%282%283%29%29\" Square \"9\" to get \"81\". \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-9+%2B-+sqrt%28+81-48+%29%29%2F%282%283%29%29\" Multiply \"4%283%29%284%29\" to get \"48\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-9+%2B-+sqrt%28+33+%29%29%2F%282%283%29%29\" Subtract \"48\" from \"81\" to get \"33\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-9+%2B-+sqrt%28+33+%29%29%2F%286%29\" Multiply \"2\" and \"3\" to get \"6\". \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-9%2Bsqrt%2833%29%29%2F%286%29\" or \"x+=+%28-9-sqrt%2833%29%29%2F%286%29\" Break up the expression. \r
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\n" ); document.write( "\n" ); document.write( "So our answers are \"x+=+%28-9%2Bsqrt%2833%29%29%2F%286%29\" or \"x+=+%28-9-sqrt%2833%29%29%2F%286%29\" \r
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\n" ); document.write( "\n" ); document.write( "which approximate to \"x=-0.543\" or \"x=-2.457\"
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