申論題

1. (25 points) Enjoy the beauty of the simplex method. Let us solve the following linear programming problem by the simplex method without tabular forms. (Please DO NOT use tabular forms to solve it.)
  

(b) (5 points) There are totally six variables, x₁, x₂,X₃,X₄, X₅,X₆, with only four equations. Four out of six variabies can be expressed by the remaining two variables. For example, x₃ is cxpressed by x₁ and X₂. Similarly, x₄, x₅, x₆ arc expressed by X₁ and x₂ as well. Since we would like to increase z, let us increase x, from zero. To kecp the feasibility, what is the maximum value we are able to increase the value in x₁?