Answer:
(a): 26.1
(b): 27.9
Please see below for the steps.
Step-by-step explanation:
(a):
Use points (0,0) and (3, 78.3)
Use slope formula. The slope formula is also used to find average rate of change (just so you know).
y2-y1/x2-x1
78.3-0/3-0=78.3/3=26.1
Answer for (a) is 26.1
(b):
Use points (4, 147.6) and (9, 287.1)
Use slope formula.
y2-y1/x2-x1
287.1-147.6/9-4=139.5/5=27.9
The answer for (b) is 27.9
Hope this helps!
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