I am stuck in the following problem:
maximize z=$x_1+2x_2+3x_3-4x_4$
subject to
$2x_1+3x_2-x_3-x_4=15$
$6x_1+x_2+x_3-3x_4=21$
$8x_1+2x_2+3x_3-4x_4=30$
$x_1,x_2,x_3,x_4$$\ge0$
then,$x_1=4,x_2=3,x_3=0,x_4=2$ is
(a) an optimal solution
(b)a degenerate basic feasible solution
(c)a non degenerate basic feasible solution
(d)a non basic feasible solution
the way i tried:
we have,4-3=1 non basic variable.so,equation $x_3$=0,we get the given solution as basic as well as non degenerate,so,according to me answer is (c)but answer is given to be (d).
any help would be appericiated