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x in (-oo:+oo)
x-((4/3)*x^2)-(12*x) = 0
(-4/3)*x^2+x-12*x = 0
-4/3*x^2-11*x = 0
DELTA = (-11)^2-(-4/3*0*4)
DELTA = 121
DELTA > 0
x = (121^(1/2)+11)/(-4/3*2) or x = (11-121^(1/2))/(-4/3*2)
x = -33/4 or x = 0
x in { -33/4, 0 }
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