maximize Z

$=$

$2$

x

$\_$

$1$

$+$

$3$

x

$\_$

$2$

$$

subject to

$$x

$\_$

$1$

$+$

$2$

x

$\_$

$2$

$<$

$=$

$4$

$,$

$$

x

$\_$

$1$

$+$

$$x

$\_$

$2$

$=$

$3$introduce an artificial variable to reformulate this problem as a convenient artificial problem for preparing to apply the simplex method.