In the context of the simplex method, "slacks" refer to the surplus variables that are introduced to convert a system of linear inequalities into a system of linear equations.

additional variables that are introduced into the linear constraints of a linear program

it is a variable that is added to an inequality constraint to transform it into an equality.

it is the excess in the variable in a problem

The definition of slack in Simplex Method is it used to convert inequalities to equalities

Slack variables help in converting the feasible region defined by inequalities into a form suitable for the simplex algorithm, which operates on equalities.