Consider the following LP model:

Maximize z = 3x1 + 2x2 + 5x3

Subject to

X1 + 2x2 + x3 + x4 = 30

3x1 + 2x3 + x5 = 60

X1 + 4x2 + x6 = 20

X1, x2, x3, x4, x5, x6 ≥ 0

Check the optimality and feasibility basic solutions:

(a) Basic variables = (x₄, x₃, x₆), Inverse = 

(b) Basic variable = (x₂, x₃, x₁), Inverse = 

(c) Basic variable = (x₂, x₃, x₆), Inverse = 

to 1. IN-IN