*4. The following is an optimal LP tableau:

Basic Xl X2 X3 X4 Xs Z 0 0 0 3 2 X3 0 0 1 1 -1 X2 0 1 0 1 0 Xl 1 0 0 -1 1 Solution

?

2 6

2 The variables X3, X4, and Xs are slacks in the original problem. Use matrix manipulations to reconstruct the original LP, and then compute the optimum value.