Question

Rate of change?

Answer 1

in general, rate of change from x = a to x = b is

[f(b) - f(a)] / (b - a) [the order is important]

so in our problem, it's from x = 2 to x = 6

so your formula ends up being

[f(6) - f(2)] / (6 - 2) = ?

Answer 2

4?

Answer 3

4f

Answer 4

to evaluate f(6) - f(2) you need to use the given function, plug in x = 6 to get f(6), plug in x = 2 to get f(2)

Answer 5

so f(x) = x^2 + 5x - 8

f(6) = ?
f(2) = ?

Answer 6

f(6) = 12
f(2) = 4
?

Answer 7

f(6) = 36 *

Answer 8

check your calculations again

f(6) = 6^2 + 5(6) - 8 = ?
f(2) = 2^2 + 5(2) - 8 = ?

remember order of operations

Answer 9

f(6)=36+30-8=58
f(2)=4+10-8=6
??

Answer 10

sorry if im getting this wrong

Answer 11

awesome

so going back to the original formula

[f(6) - f(2)] / (6 - 2) = (58 - 6) / (6 - 2) = 13 = your sol'n

Answer 12

so 13 is the average rate of change?

Answer 13

yes

Answer 14

thank you!