f(x)=3x2−3 between each of the pairs of points below. Between (5,72) and (8,189)

Question

Find the average rate of change of f(x)=3x2−3 between each of the pairs of points below.

(a) Between (5,72) and (8,189)

Answer 1

2 points: (5,72) & (8,189)

deltax=8-5=3

deltay=189-72=117

slope=deltay/deltax=117/3=39

thats the slope av a strate line thru 2 points

Answer 2

Average rate of change is just the change in y (f (x)) over the change in x, a.k.a, the slope of the secant line
You might remember slopes from Algebra 1. "m" from y = mx + b
m = (y2 - y1) / (x2 - x1)
(5,72) and (8,189)
m=(189-72)/(8-5)
m=39

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