Step-by-step explanation:
The number line below describes number larger than 2.
This can be written as {x: x > 2}.
Note that the indicator on 2 is not shaded, this shows that 2 is not included in the set.
..|......|......|......|......|......|......|......|......|......|..
-2....-1.....0....1.....2.....3....4.....5....6.....7
............................O-------------------------->
.......................................(x > 2)
The number line below describes number smaller than 5. This can be written as {x: x < 5}. 5 is not included in this set neither, so, the indicator is also not shaded.
..|......|......|......|......|......|......|......|......|......|..
-2....-1.....0....1.....2.....3....4.....5....6.....7
<-------------------------------------O
...............(x < 5)
LOOK AT THIS EXAMPLE BELOW
..|......|......|......|......|......|......|......|......|......|..
-2....-1.....0....1.....2.....3....4.....5....6.....7
<--------------------------------•
...............(x ≤ 4)
Note that the indicator on 4 is shaded black. It shows that 4 is included in the set.