Answer: rise over run
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Explanation:
The rate of change is the same as slope. Slope is often defined as the ratio of rise over run.
In other words, slope = rise/run.
For instance, a slope of 2/3 means we go up 2 and to the right 3 units.
Another example: slope = -1/5 means we go down 1 and to the right 5.
The term "rise" indicates a change in y. The run is the change in x. If the rise is positive, then you go up. Negative rise values mean that you go down. The run always moves to the right.
