A question such as: "for which $x$ is 6 – x > 0.5x?" is an example of an inequality.

Such an inequality is solved by drawing the graphs of `y_1=6-x` en `y_2= 0,5x` . You see that `y_1=y_2` when `x=4` , `y_1>y_2` when `x < 4` and `y_1 < y_2` when `x>4` .

The answer to the question, the solution to the inequality, is therefore x < 4.

In a similar fashion you can deal with inequalities which consider "is less than" ( < ), "is less than or equal" ( $\le$) or "is greater than or equal" ( $\ge$).