Water coming out from a fountain is modeled by the function f(x) = −x2 + 8x + 2 where f(x) represents the height, in feet, of the water from the fountain at different times x, in seconds.

What does the average rate of change of f(x) from x = 1 to x = 4 represent?

Question

Water coming out from a fountain is modeled by the function f(x) = −x2 + 8x + 2 where f(x) represents the height, in feet, of the water from the fountain at different times x, in seconds.

What does the average rate of change of f(x) from x = 1 to x = 4 represent?

anonymous · Answer

A)The water travels an average distance of 3 feet from 1 second to 4 seconds.
 B)The water travels an average distance of 2 feet from 1 second to 4 seconds.
 C)The water rises up with an average speed of 3 feet per second from 1 second to 4 seconds.
 D)The water rises up with an average speed of 2 feet per second from 1 second to 4 seconds.

anonymous · Answer

@Hero @dan815

anonymous · Answer

@muscrat123

campbell_st · Answer

find the slope of the for the average rate of change between x = 1 and x= 4

1st step is find the value of

f(1) 

then 

F(4) 

the the average rate of change is 

$$avg ~rate~of~change = \frac{f(4) - f(1)}{4 - 1}$$

then read the answer choices to see which matches

anonymous · Answer

i think C? IM right? @campbell_st

campbell_st · Answer

that's correct

anonymous · Answer

thank you so much can you help me with 2 more please?