The set of values that satisfy an equation or inequality.

### Examples

- In \(\mathbb{N}\), the solution set of the equation
*x*+ 9 = 15 is {6}. - In \(\mathbb{N}\), the solution set of the inequality
*x*+ 9 ≤ 15 is {0, 1, 2, 3, 4, 5, 6}. - In \(\mathbb{R}\), the solution set of the inequality
*x*+ 9 ≤ 15 is {*x*∈ \(\mathbb{R}\) |*x*≤ 6} or ] –∞, 6]. - In \(\mathbb{R}\), the solution set of the inequality 3
*x*≥ 15 is {*x*∈ \(\mathbb{R}\) |*x*≥ 3} or [3, –∞[.