To use the Constraints panel in Advanced Entry mode:
Switch to Advanced Entry mode by selecting Advanced Entry in the corner of the Constraints editor.
In the Constraints editor, enter a mathematical formula. You can use the buttons at the bottom of the Constraints panel to help you edit the formula.
For information on the Constraints editor syntax, see Constraint Rules and Syntax.
You can also enter parts of a constraint formula into spreadsheet cells and then reference those cells, separated by an operator, in a formula. See Constraints and Cell References in Advanced Entry Mode.