document.write( "Question 229209: 2x^2-4x-1=0\r
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\n" ); document.write( "\n" ); document.write( "answer: 2 + sqrt6 /2 , or 2 - sqrt6/2 anyone can give me a full break down of why trhe answer is 2 + sqrt 6/2 or 2 - sqrt6/2 \n" ); document.write( "
Algebra.Com's Answer #169972 by stanbon(75887)\"\" \"About 
You can put this solution on YOUR website!
2x^2-4x-1=0
\n" ); document.write( "This is a quadratic with a = 2 ; b = -4 ; and c = -1
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\n" ); document.write( "Use the Quadratic Formula:
\n" ); document.write( "x = [-b +- sqrt(b^2 - 4ac)]/(2a)
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\n" ); document.write( "Plug in the values for a, b, and c to get:
\n" ); document.write( "x = [4 +- sqrt(16 - 4*2*-1)]/4
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\n" ); document.write( "x = [4 +- sqrt(24)]/4
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\n" ); document.write( "x = [4 +- 2sqrt(6)]/4
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\n" ); document.write( "x = (1 + (1/2)sqrt(6)) or x = (1- (1/2)sqrt(6))
\n" ); document.write( "This can be written:
\n" ); document.write( "x = (2+sqrt(6))/2 or x = (2-sqrt(6))/2\r
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\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H. \n" ); document.write( "
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