An inequality or in-equation is an expression involving an inequality sign that is >, <, ≤, ≥, that is greater than, equal or less to, less than, greater or equal to the given are some examples of in-equations in variable as:
3x + 3 > 5
x2 - 2x - 12 < 0
There is the first example of linear in-equation and the second example of a quadratic in equation.