When an ordered pair is in a shared region it means that the ordered pair is a solution to the inequality.
If an ordered pair is on the line of an inequality, it may or may not be a solution. If the inequality is a ≤ ≥ then the point on the line will be a solution because the line is part of the solution. If the inequality is a > < then the point t on the line will not be a solution because the line is not part of the solution.