document.write( "Question 102534: I am having problems with this one\r
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Algebra.Com's Answer #74569 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
\"x%5E2=-5x-5\" Start with the given quadratic\r
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\n" ); document.write( "\n" ); document.write( "\"0=-x%5E2-5x-5\" Subtract \"x%5E2\" from both sides\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( "Starting with the general quadratic\r
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\n" ); document.write( "\n" ); document.write( "\"ax%5E2%2Bbx%2Bc=0\"\r
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\n" ); document.write( "\n" ); document.write( "the general solution using the quadratic equation is:\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29\"\r
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\n" ); document.write( "\n" ); document.write( "So lets solve \"-x%5E2-5%2Ax-5=0\" ( notice \"a=-1\", \"b=-5\", and \"c=-5\")\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28--5+%2B-+sqrt%28+%28-5%29%5E2-4%2A-1%2A-5+%29%29%2F%282%2A-1%29\" Plug in a=-1, b=-5, and c=-5\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%285+%2B-+sqrt%28+%28-5%29%5E2-4%2A-1%2A-5+%29%29%2F%282%2A-1%29\" Negate -5 to get 5\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%285+%2B-+sqrt%28+25-4%2A-1%2A-5+%29%29%2F%282%2A-1%29\" Square -5 to get 25 (note: remember when you square -5, you must square the negative as well. This is because \"%28-5%29%5E2=-5%2A-5=25\".)\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%285+%2B-+sqrt%28+25%2B-20+%29%29%2F%282%2A-1%29\" Multiply \"-4%2A-5%2A-1\" to get \"-20\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%285+%2B-+sqrt%28+5+%29%29%2F%282%2A-1%29\" Combine like terms in the radicand (everything under the square root)\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%285+%2B-+sqrt%285%29%29%2F%282%2A-1%29\" Simplify the square root (note: If you need help with simplifying the square root, check out this solver)\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%285+%2B-+sqrt%285%29%29%2F-2\" Multiply 2 and -1 to get -2\r
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\n" ); document.write( "\n" ); document.write( "So now the expression breaks down into two parts\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%285+%2B+sqrt%285%29%29%2F-2\" or \"x+=+%285+-+sqrt%285%29%29%2F-2\"\r
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\n" ); document.write( "\n" ); document.write( "Now break up the fraction\r
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\n" ); document.write( "\n" ); document.write( "\"x=%2B5%2F-2%2Bsqrt%285%29%2F-2\" or \"x=%2B5%2F-2-sqrt%285%29%2F-2\"\r
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\n" ); document.write( "\n" ); document.write( "Simplify\r
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\n" ); document.write( "\n" ); document.write( "\"x=-5+%2F+2-sqrt%285%29%2F2\" or \"x=-5+%2F+2%2Bsqrt%285%29%2F2\"\r
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\n" ); document.write( "\n" ); document.write( "So these expressions approximate to\r
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\n" ); document.write( "\n" ); document.write( "\"x=-3.61803398874989\" or \"x=-1.38196601125011\"\r
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\n" ); document.write( "\n" ); document.write( "So our solutions are:\r
\n" ); document.write( "\n" ); document.write( "\"x=-3.61803398874989\" or \"x=-1.38196601125011\"\r
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\n" ); document.write( "\n" ); document.write( "Notice when we graph \"-x%5E2-5%2Ax-5\", we get:\r
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\n" ); document.write( "\n" ); document.write( "when we use the root finder feature on a calculator, we find that \"x=-3.61803398874989\" and \"x=-1.38196601125011\".So this verifies our answer
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