Add Constraint and Change Constraint
Cell Reference Specifies the cell or range of cells where you want to constrain the values.
Constraint Specifies a restriction on the contents of the Cell Reference box. Select the relationship that you want to add or change ( <=, =, >=, int, or bin ) between the referenced cell and the constraint. Then enter the constraint - a number, cell or range reference, or formula - in the box to the right.
Add Click to add another constraint without returning to the Solver Parameters dialog box.