Question 206073
multiply  thru  by  4x
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4x^3 -9 -100x =0,,,,or  4x^3 -100x -9 =0
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solving  for  roots  x=  approx,,,-.09,,,-4.95,,,,+5.05
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to  factor  original,,,,
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x^2 -9/4x -25 =0
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x^2 -25 = 9/4x
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(x+5)(x-5) =9/4x
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(4x)(x+5)(x-5) =9
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if  this  equaled  0,  x=0,-5,+5,,,,,,,,but  for  9  see  above  approximation
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