Answer: Choice A is correct
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Step-by-step explanation:
Each time x goes up by 1, y goes up by 100 (eg: from 50 to 150, so 150-50 = 100).
We then say,
slope = rise/run
slope = (change in y)/(change in x)
slope = (100)/(1)
slope = 100
The rate of change is $100 per deposit
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We could also use the slope formula. Pick any two points on the diagonal line. Let's say we picked (1,150) and (3,350)
m = (y2-y1)/(x2-x1)
m = (350-150)/(3-1)
m = (200)/(2)
m = 100
Or we could pick (0,50) and (1,150) as our two points
m = (y2-y1)/(x2-x1)
m = (150-50)/(1-0)
m = (100)/(1)
m = 100
Either way, the slope is m = 100.