A constraint is a restriction or limitation on the possible solutions of a problem or system. In the context of a system of inequalities, a constraint is an inequality that must be satisfied by any solution of the system. A system of inequalities is a set of multiple inequalities that must all be satisfied simultaneously. Solving a system of inequalities involves finding the set of all possible solutions that satisfy all of the constraints. This can be done graphically by graphing the inequalities and finding the intersection of their solution sets, or algebraically by isolating the variables and solving for their values.