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x in (-oo:+oo)
x*((4*x+3)/12) = 36 // - 36
x*((4*x+3)/12)-36 = 0
(x*(4*x+3))/12-36 = 0
(x*(4*x+3))/12+(-36*12)/12 = 0
x*(4*x+3)-36*12 = 0
4*x^2+3*x-432 = 0
4*x^2+3*x-432 = 0
4*x^2+3*x-432 = 0
DELTA = 3^2-(-432*4*4)
DELTA = 6921
DELTA > 0
x = (6921^(1/2)-3)/(2*4) or x = (-6921^(1/2)-3)/(2*4)
x = (3*769^(1/2)-3)/8 or x = (-3*769^(1/2)-3)/8
(x-((-3*769^(1/2)-3)/8))*(x-((3*769^(1/2)-3)/8)) = 0
((x-((-3*769^(1/2)-3)/8))*(x-((3*769^(1/2)-3)/8)))/12 = 0
((x-((-3*769^(1/2)-3)/8))*(x-((3*769^(1/2)-3)/8)))/12 = 0 // * 12
(x-((-3*769^(1/2)-3)/8))*(x-((3*769^(1/2)-3)/8)) = 0
( x-((-3*769^(1/2)-3)/8) )
x-((-3*769^(1/2)-3)/8) = 0 // + (-3*769^(1/2)-3)/8
x = (-3*769^(1/2)-3)/8
( x-((3*769^(1/2)-3)/8) )
x-((3*769^(1/2)-3)/8) = 0 // + (3*769^(1/2)-3)/8
x = (3*769^(1/2)-3)/8
x in { (-3*769^(1/2)-3)/8, (3*769^(1/2)-3)/8 }
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