Write the dual of the program explicitly, and put the program and its dual in a single tableau. If the program is a minimum program, write the dual $($maximum$)$ program across in the tableau and the original $($minimum$)$ program down in the tableau. Finally, find the optimal solutions to both programs. Maximize u$=$x$-$y$-$z$,$ subject to x$-$y$+$z$5,$ x$+$y$-$z$3,$ x$,$y$,$z$0.$