Question

check my work??
5.) kim is studying the sale of a particular brand of cereals from the year 2000 to 2010. She writes the following functions to model the sale of the cereal S(t) in million dollars after t years.
S(t)=t^2+7t +69
Part a. what does the y-intercept of the graph of the function represent?

the sale of the cereal at the start

Part B: What is the reasonable domain of the graph of the function?

The domain is the time from 2000 to 2010

Part C: What is the average rate of change of the sale of the cereal from the first year to the fourth year?

t^2 + 7t + 69
4^2 + 7(4) +69
16 + 28 + 69=113

Answer 1

does it look right?@thomaster

Answer 2

@thomaster

Answer 3

@tHe_FiZiCx99

Answer 4

B and C are wrong

Answer 5

A reasonable domain for this function would be: 200 ≥ x ≤ 2010 because she's studying from the year 2000 to the year 2010.

Answer 6

what wrong with c?

Answer 7

To find the average rate of change apply change in y all over change in x. (y - y)/(x - x). In this case it's change in y all over change in t, (y - y)/(t - t)

Answer 8

Set it up, tag me when you're done simplifying, plug in t = 1 and t = 4 into your function

Answer 9

S(t)=t^2+7t +69

S(1)=4^2+7(4) +69
s(1)=16+28+69
73?
@tHe_FiZiCx99

Answer 10

How did you get 73?

Answer 11

16 + 28 + 69 = 113

So (4,113)

And when you plug in 1 for t you get (1,77)

so \(\ \sf \dfrac{113-77}{4-1} = \dfrac{36}{3} = 12\)

So the average rate of change between the \(\ \sf 4^{th}\)year and \(\ \sf 1^{st}\)is 12.

Answer 12

ohhhh okay I see can you help me with another one? @tHe_FiZiCx99

Answer 13

If I can, I'm getting off soon