Answer
Positive rate of change means that the function is increasing. Negative rate of change means that the function is decreasing.
Work Step by Step
Graph 2 lines: one with a positive rate of change and one with a negative rate of changed. I graphed $y = x$ (red) and $y = -x$(black). The positive rate of change graph (red) is increasing while the negative rate of change graph (black) is decreasing.
