The highest point is when y = 0 and the lowest point is when y = -5
We can see this if we draw horizontal lines through the highest and lowest points (see the diagram below). Note where the horizontal lines cross the y axis. For y = 0, we don't really need a horizontal line but I'll draw it anyway.
Since y ranges from y = -5 to y =0, the range is therefore [tex]-5 \le y \le 0[/tex]
Answer: y is a real number such that [tex]-5 \le y \le 0[/tex]
Side note: to write this in interval notation, you would say [tex][-5, 0][/tex]. The square brackets say to include each endpoint as part of the range.
