Linear Algebra and Its Applications · Problem 8.2.10
Linear Programming and Game Theory — Gilbert Strang
Mathematics · simplex-method-entering-leaving
Problem
Suppose we want to minimize cx=x1−x2, subject to
2x1−4x2+x3=63x1+6x2−4x2+x4=12
(all x1,x2,x3,x4≥0).
Starting from x=(0,0,6,12), should x1 or x2 be increased from its current value of zero? How far can it be increased until the equations force x3 or x4 down to zero? At that point, what is the new x?