document.write( "Question 87585: x^2=5x-1\r
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Algebra.Com's Answer #63511 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
\"x%5E2=5x-1\"\r
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\n" ); document.write( "\n" ); document.write( "\"x%5E2-5x%2B1=0\" Get everything to one side\r
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\n" ); document.write( "\n" ); document.write( "Now let's use the quadratic formula to solve for x:\r
\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 form of 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%2B1=0\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%285+%2B-+sqrt%28+%28-5%29%5E2-4%2A1%2A1+%29%29%2F%282%2A1%29\" Plug in a=1, b=-5, and c=1\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%285+%2B-+sqrt%28+25-4%2A1%2A1+%29%29%2F%282%2A1%29\" Square -5 to get 25\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%285+%2B-+sqrt%28+25%2B-4+%29%29%2F%282%2A1%29\" Multiply \"-4%2A1%2A1\" to get \"-4\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%285+%2B-+sqrt%28+21+%29%29%2F%282%2A1%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%2821%29%29%2F%282%2A1%29\" Simplify the square root\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%285+%2B-+sqrt%2821%29%29%2F2\" 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%2821%29%29%2F2\" or \"x+=+%285+-+sqrt%2821%29%29%2F2\"\r
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\n" ); document.write( "\n" ); document.write( "Which approximate to\r
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\n" ); document.write( "\n" ); document.write( "\"x=4.79128784747792\" or \"x=0.20871215252208\"\r
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\n" ); document.write( "\n" ); document.write( "So our solutions are:\r
\n" ); document.write( "\n" ); document.write( "\"x=4.79128784747792\" or \"x=0.20871215252208\"\r
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\n" ); document.write( "\n" ); document.write( "Notice when we graph \"x%5E2-5%2Ax%2B1\" 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=4.79128784747792\" and \"x=0.20871215252208\".So this verifies our answer
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