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x in (-oo:+oo)
11.5 = x*((13*x+139)/13) // - x*((13*x+139)/13)
11.5-(x*((13*x+139)/13)) = 0
(-1*x*(13*x+139))/13+11.5 = 0
(-1*x*(13*x+139))/13+(11.5*13)/13 = 0
11.5*13-1*x*(13*x+139) = 0
149.5-13*x^2-139*x = 0
149.5-13*x^2-139*x = 0
149.5-13*x^2-139*x = 0
DELTA = (-139)^2-(-13*4*149.5)
DELTA = 27095
DELTA > 0
x = (27095^(1/2)+139)/(-13*2) or x = (139-27095^(1/2))/(-13*2)
x = (27095^(1/2)+139)/(-26) or x = (139-27095^(1/2))/(-26)
(x-((27095^(1/2)+139)/(-26)))*(x-((139-27095^(1/2))/(-26))) = 0
((x-((27095^(1/2)+139)/(-26)))*(x-((139-27095^(1/2))/(-26))))/13 = 0
((x-((27095^(1/2)+139)/(-26)))*(x-((139-27095^(1/2))/(-26))))/13 = 0 // * 13
(x-((27095^(1/2)+139)/(-26)))*(x-((139-27095^(1/2))/(-26))) = 0
( x-((139-27095^(1/2))/(-26)) )
x-((139-27095^(1/2))/(-26)) = 0 // + (139-27095^(1/2))/(-26)
x = (139-27095^(1/2))/(-26)
( x-((27095^(1/2)+139)/(-26)) )
x-((27095^(1/2)+139)/(-26)) = 0 // + (27095^(1/2)+139)/(-26)
x = (27095^(1/2)+139)/(-26)
x in { (139-27095^(1/2))/(-26), (27095^(1/2)+139)/(-26) }
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