Consider the following linear programming problem

$mi{n}_{x_1,x_2},4x_1+3x_2$

$,x_1+x_{2}40,$

$,2x_1+x_{2}60,$

$,x_1,x_{2}0,$

and its reformulation in standard form

$mi{n}_{x_1,x_2,x_3,x_4},4x_1+3x_2$

$,x_1+x_2+x_3=40,$

$,2x_1+x_2+x_4=60,$

$,x_1,x_2,x_3,x_{4}0.$

d$)$ Solve the problem using the Simplex algorithm, starting from the

feasible basic solution $(x_1=20,x_2=20,x_3=0,x_4=0).$Observe

which extreme points of the feasible region of $($LP$)$ are visited at each

iteration of the Simplex algorithm.