Solution Region
The representation of the solution set of a relationship in a Cartesian plane.
The solution set of a relationship (equation, inequality, function, etc.) is a set of ordered pairs that describes the relationship in roster form (tabular form). The set of ordered pairs can be represented in a Cartesian plane to form a continuous span of points called a region.
When the solution set of a relationship is a point, a line or a curve, the expression "solution region" is less appropriate.
