maximize 6x₁ + 8x2 + 5x3+9x4 subject to x₁ + x₂ + x3 + x₁ = 1 X1, X2, x3, x4 ≥ 0. list all basic sets. basic feasible solutions. the simplex algorithm). find and (do not use Check the value of the objective all basic feasible solutions. at the problem. to all function solve