An interval is a range of numbers. We can use the graphs of inequalities to represent intervals because they show a starting point and end point, and the region between the points. The points are shown by either closed or open circles, while the region between them is shaded. To visualize this, we can consider an example. Suppose x can be any value in the interval (2, 7]. This means that the following inequalities hold true.
x>2 and x≤7