1. The problem statement, all variables and given/known data I need to rewrite this equation as a function of y. would love some help since i failed on the right side of the equation. v= [πr(3R-y)y²]/3R + L√[(2R-y)y(y-R)+R²cos^-1(1- y/R)] i mean is it even possible to get y out of there, with inverse cosine and all? Thanks in advance. @gabbagabbahey there isn't any original question. i wanted to get this equation in order to use in calculating the liquid height in an LPG tank. The equation above gives the liquid volume in the tank as long as you have the liquid height. i want to make use of it in reverse. i have the liquid volume and want to calculate the liquid height.