Answer: rate of change = 2
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Explanation:
Apply the slope formula. I'll use the first two columns as the two points, but you can use any two columns you want.
m = (y2-y1)/(x2-x1)
m = (9-5)/(3-1)
m = 4/2
m = 2
The slope is 2, so the rate of change is 2. Slope and rate of change describe the same thing. Each time x goes up by 1, y goes up by 2.
