Show that the dual variables corresponding to equality constraints in a primal problem are unrestricted in sign. (Hint: Convert the primal equality constraints into two inequality constraints in...

Show that the dual variables corresponding to equality constraints in a primal problem are unrestricted in sign. (Hint: Convert the primal equality constraints into two inequality constraints in canonical form. Associate dual variables with each of the corresponding constraints. Show that the new dual variables appear as pairs that can be converted into one unconstrained variable.)