<PRE><B>Question 335690</B>
quadratic equation 
x^2 - 4x - 7 =0 
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a = 1 ; b = -4 ; c = -7
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x = [-b +- sqrt(b^2-4ac)]/(2a)
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x = [4 +- sqrt(16-4*1*-7)]/(2*1)
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x = [4 +- sqrt(16+28)]/2
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x = [4 +- sqrt(44)]/2
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x = [4 +- sqrt(4*11)]/2
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x = [4 +- 2*sqrt(11)]/2
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x = [2 +- sqrt(11)]
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x = 2+sqrt(11) or x = 2-sqrt(11)
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Cheers,
Stan H.</PRE>