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12*x^2-(81*x)-(3/7) = 0
12*x^2-81*x-3/7 = 0
12*x^2-81*x-3/7 = 0
DELTA = (-81)^2-(-3/7*4*12)
DELTA = 46071/7
DELTA > 0
x = ((46071/7)^(1/2)+81)/(2*12) or x = (81-(46071/7)^(1/2))/(2*12)
x = ((46071/7)^(1/2)+81)/24 or x = (81-(46071/7)^(1/2))/24
x in { (81-(46071/7)^(1/2))/24, ((46071/7)^(1/2)+81)/24 }
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