Slack form of a linear program ($x_B=b-A{x}_N,z=v+c^T{x}_N$)

An equality representation of a linear program in which each basic variable and the objective function are expressed using nonbasic variables, and all variables are nonnegative. Introducing slack variables into $Ax\le b$ gives $s=b-Ax$. Setting the nonbasic variables to zero yields its basic solution; nonnegative resulting basic values make this a basic feasible solution. A simplex algorithm pivot exchanges a basic and nonbasic index and rewrites these expressions.