Am I using the correct quadratic equation for this chemistry problem?

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The quadratic equation x = (-b ± √(b² - 4ac)) / 2a is valid even when the discriminant (b² - 4ac) is negative, leading to complex roots. In analytical chemistry applications, a negative discriminant may indicate an error in the input values or an unrealistic scenario being modeled. It's essential to verify that the correct values for a, b, and c are used in the equation. If the equation yields complex numbers, it suggests that the situation may not have a real solution. Ultimately, the appropriateness of the quadratic equation depends on the context and the accuracy of the input parameters.
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For our typical quadratic equation:

x= (-b± \sqrt{b^2-4ac})/2a


Am I missing something? I mean the value underneath the square root turns out to be a negative number, so technically this equation would not have worked right? It's from a textbook by the way. This is actually an analytical chemistry application question.

x= -6.8*10-4 ± [(6.8*10-4)2 - (4)(6.8*10-4)]0.5/(2)(1)
 
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The equation works fine with negative numbers. Sometimes this happens when the roots should be real, either a mistake was made or the situation modeled is impossible or there was rounding and the roots returned are barely complex and should be rounded back to real.
 
is b = c ?
or did you write the wrong value?

In any case, negative ARE possible and you go into complex number territory
 
If a proper math equation (which this is) is applied in a way that doesn't give a physically possible answer, that's not the math's fault and you need to look at whether or not the right numbers have been put in or whether perhaps the equation is not the right one to use in a given situation.
 
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