document.write( "Question 472171: -x^2+7x=4\r
\n" ); document.write( "\n" ); document.write( "I changed it to -x^2+ 7x -4 = 0
\n" ); document.write( "and quadratic equation would be -b+/- the square root of b^2 -4ac all over 2a.
\n" ); document.write( "a=-1
\n" ); document.write( "b= 7
\n" ); document.write( "c= -4
\n" ); document.write( "and I got 7.5 and 0.5 but when I plug it back in it does not work!
\n" ); document.write( "Help is MUCH appreciated!
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Algebra.Com's Answer #323770 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
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\n" ); document.write( "\n" ); document.write( "\"-x%5E2%2B7x-4=0\" Start with the given equation.\r
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\n" ); document.write( "\n" ); document.write( "Notice that the quadratic \"-x%5E2%2B7x-4\" is in the form of \"Ax%5E2%2BBx%2BC\" where \"A=-1\", \"B=7\", 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-%287%29+%2B-+sqrt%28+%287%29%5E2-4%28-1%29%28-4%29+%29%29%2F%282%28-1%29%29\" Plug in \"A=-1\", \"B=7\", and \"C=-4\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-7+%2B-+sqrt%28+49-4%28-1%29%28-4%29+%29%29%2F%282%28-1%29%29\" Square \"7\" to get \"49\". \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-7+%2B-+sqrt%28+49-16+%29%29%2F%282%28-1%29%29\" Multiply \"4%28-1%29%28-4%29\" to get \"16\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-7+%2B-+sqrt%28+33+%29%29%2F%282%28-1%29%29\" Subtract \"16\" from \"49\" to get \"33\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-7+%2B-+sqrt%28+33+%29%29%2F%28-2%29\" Multiply \"2\" and \"-1\" to get \"-2\". \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-7%2Bsqrt%2833%29%29%2F%28-2%29\" or \"x+=+%28-7-sqrt%2833%29%29%2F%28-2%29\" Break up the expression. \r
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\n" ); document.write( "\n" ); document.write( "So the solutions are \"x+=+%28-7%2Bsqrt%2833%29%29%2F%28-2%29\" or \"x+=+%28-7-sqrt%2833%29%29%2F%28-2%29\" \r
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\n" ); document.write( "\n" ); document.write( "These solutions approximate to \"x+=+0.62771867673099\" or \"x+=+6.37228132326901\"
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