Find the maximum and minimum value of the objective function given.

z = 21x + 12y
maximum value z =
minimum value z =

since this is the equation of a plane, there is no max or min. Does x have a max or min? Does y?

I suspect something is missing here.

To find the maximum and minimum values of the objective function, we need to know the constraints or the region in which the variables x and y are allowed to vary. This is because the maximum and minimum values can occur at the boundaries of the feasible region or at any critical points within the region.

Without the constraints or feasible region information, we cannot determine the exact maximum and minimum values. However, if we assume that x and y can take any real values, then the objective function z = 21x + 12y will not have an absolute maximum or minimum value.

If you have the constraints or the feasible region information, please provide them so we can proceed with finding the maximum and minimum values of the objective function.