Please write by hand, that would help me understand more easily

14.8 Lagrange Multipliers Each of these extreme value problems has a solution with both a maximum value and a minimum value. Use Lagrange multipliers to find the extreme values of the function subject to the given constraint. 12. f (x, y, z) = x2+ +22, x2 + +2 +ay=12 56. Find the maximum and minimum volumes of a rectangular box whose surface area is 1500 cm and whose total edge length is 200 cm