document.write( "Question 193113: 4x^2-4x=1 \n" ); document.write( "
Algebra.Com's Answer #144951 by jim_thompson5910(35256)\"\" \"About 
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\n" ); document.write( "\n" ); document.write( "\"4x%5E2-4x=1\" Start with the given equation.\r
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\n" ); document.write( "\n" ); document.write( "\"4x%5E2-4x-1=0\" Subtract 1 from 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=4\", \"b=-4\", and \"c=-1\"\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-%28-4%29+%2B-+sqrt%28+%28-4%29%5E2-4%284%29%28-1%29+%29%29%2F%282%284%29%29\" Plug in \"a=4\", \"b=-4\", and \"c=-1\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%284+%2B-+sqrt%28+%28-4%29%5E2-4%284%29%28-1%29+%29%29%2F%282%284%29%29\" Negate \"-4\" to get \"4\". \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%284+%2B-+sqrt%28+16-4%284%29%28-1%29+%29%29%2F%282%284%29%29\" Square \"-4\" to get \"16\". \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%284+%2B-+sqrt%28+16--16+%29%29%2F%282%284%29%29\" Multiply \"4%284%29%28-1%29\" to get \"-16\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%284+%2B-+sqrt%28+16%2B16+%29%29%2F%282%284%29%29\" Rewrite \"sqrt%2816--16%29\" as \"sqrt%2816%2B16%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%284+%2B-+sqrt%28+32+%29%29%2F%282%284%29%29\" Add \"16\" to \"16\" to get \"32\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%284+%2B-+sqrt%28+32+%29%29%2F%288%29\" Multiply \"2\" and \"4\" to get \"8\". \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%284+%2B-+4%2Asqrt%282%29%29%2F%288%29\" Simplify the square root \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%284%2B4%2Asqrt%282%29%29%2F%288%29\" or \"x+=+%284-4%2Asqrt%282%29%29%2F%288%29\" Break up the expression. \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%281%2Bsqrt%282%29%29%2F%282%29\" or \"x+=+%281-sqrt%282%29%29%2F%282%29\" Reduce\r
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\n" ); document.write( "\n" ); document.write( "So the answers are \"x+=+%281%2Bsqrt%282%29%29%2F%282%29\" or \"x+=+%281-sqrt%282%29%29%2F%282%29\" \r
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\n" ); document.write( "\n" ); document.write( "which approximate to \"x=1.207\" or \"x=-0.207\"
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