How do i write the interval(s) for which f(x) is greater than or equal to 0 (interval notation)

We are looking for the set of values for which y is greater than 0. This would be negative infinity to -2, but not including
-2. This could be expressed as (-infinity, -2). Also, all x values greater than 0 also lead to a y-value greater than 0. Thus, another interval would be (0, infinity). Thus, the answer is (-infinity, -2) and (0, infinity).

Answer 20 centimeters15+8=2323-3=20so the answer is 20 centimeters

There is no graph to go along with this