Question

The function below shows the number of car owners f(t), in thousand, in a city in different years t:

f(t) = 0.25t2 - 1.5t + 2.5

The average rate of change of f(t) from t = 5 to t = 8 is ______ thousand per year

Answer 1

@austinL

Answer 2

@jigglypuff314

Answer 3

need help

Answer 4

yeah.. lol

Answer 5

what can help you with

Answer 6

the problem..lol

Answer 7

are awarding medals

Answer 8

@tHe_FiZiCx99

Answer 9

yeah...

Answer 10

plug in t=5 into the equation get number
then plug in t=8 into equation and get another number
then find slope (avg rate of change)
which is second number minus first number
divided by 8-5

Answer 11

Average rate of change is f(b) - f(a)/b-a

Answer 12

f(b) is 8 and f(a) is 5

Find the value of (5) and f(8) first

Answer 13

f(t)=0.25t2−1.5t+2.5?

Answer 14

have no idea

Answer 15

@jigglypuff314

Answer 16

simplify
0.25(5)^2 - 1.5(5) + 2.5

then simplify
0.25(8)^2 - 1.5(8) + 2.5

Answer 17

1.25,6.5

Answer 18

yep
then do 6.5-1.5
--------- = ?
8 - 5

Answer 19

Remember to first do the exponents, 5^2 = 25

0.25*25 = 6.25

So f(5) = 6.25

Answer 20

Oh i missed the 1.5t >_<

Answer 21

@jigglypuff314 5/3?

Answer 22

yeah, I think that's it :)

Answer 23

your great thanks !

Answer 24

f(5) = 0.25(5)^2 - 1.5(5) + 2.5
f(5) = 0.25*25 - 7.5 + 2.5
f(5) = 6.25 - 7.5 + 2.5
f(5) = 1.25

Same for f(8),

f(8) = 6.5

6.5 - 1.25
----------
8 - 5

5.25
-----
3

So the average rate of change is 1.75 from 5 to 8 or 8 to 5

Answer 25

ah right, mistake on my part @desmonds
@tHe_FiZiCx99 is right :)

Answer 26

so it's 1.75?

Answer 27

@tHe_FiZiCx99

Answer 28

I think so :3

Answer 29

lol you think :x

Answer 30

What're that options :> if you have a doubt I'll double check it >_<

Answer 31

lol ok i'll go with 1.75

Answer 32

o.0

Answer 33

why the face lol?

Answer 34

Thought you had option >.>

Answer 35

options*