1. The problem statement, all variables and given/known data When a rectangular box is sent through the mail, the post office demands that the length of the box plus twice the sum of its height and width be no more than 250 centimeters. Find the dimensions of the box satisfying this requirement that encloses the largest possible volume. (Solve this problem without using Lagrange multipliers.) 2. Relevant equations Partial differentiation and equations of constraint for each variable. 3. The attempt at a solution My attempt at a solution is attached however, given that I got length = l = 0 (even though I get a nonzero width and height) which gives a volume of 0, I'd say I did something wrong and I don't have the solutions or answer for this particular problem so I can't check what's wrong.