 It is easily seen to be optimal since the objective row now corresponds to an equation of the form 

By changing the entering variable choice rule so that it selects a column where the entry in the objective row is negative, the algorithm is changed so that it finds the maximum of the objective function rather than the minimum.Once the pivot column has been selected, the choice of pivot row is largely determined by the requirement that the resulting solution be feasible.First, only positive entries in the pivot column are considered since this guarantees that the value of the entering variable will be nonnegative.