You can
put this solution on YOUR website!what do you mean by " how to make x as subject in the equation ".
also question seems vague. is it y= (4/x^2) + (5x + 8/x^2) correct.
y= (4/x^2) + (5x + 8/x^2)
= (12/x^2) + 5x
= (12 + 5 x^3)/(x^2)
Please post the question again if the equation is wrong.
thanks