wow need some assistance

[TYSONG]

Give an appropriate answer.

Find the instantaneous rate of change for the function x^2 + 6x at x = 8.

a. 112
b. 16
c. 22
d. 14


what do I do? I am soooo lost.

 

[Unco]

The rate of change of the function f(x) = x^2 + 6x is found by differentiating:

f'(x) = ?

The instantaneous rate of change (with respect to x) at x=8 is given by plugging x=8 into f'(x).

 

[stapel]

As noted in a previous reply, finding the "instantaneous rate of change" requires differentiation, a tool of calculus. But you posted this question to one of the "algebra" categories, so presumably you haven't yet started calculus.

So my question then is: What sort of technique, method, or formula are you, a pre-calculus student, being expected by your instructor to use for this exercise?

Thank you.

Eliz.

 

[josh123]

I got b, I could be wrong though..........

 

[stapel]

I got b...

I'm sorry, but your answer is incorrect.

Please be considerate of the needs of your fellow students by not posting incorrect answers to their questions. Thank you.

Eliz.

 

[TYSONG]

I got 112 for my answer?

 

[Unco]

Oh, dude, what was your derivative?

Try ignoring the multi-choice and posting your work.