Westonci.ca makes finding answers easy, with a community of experts ready to provide you with the information you seek. Experience the convenience of getting reliable answers to your questions from a vast network of knowledgeable experts. Discover in-depth answers to your questions from a wide network of professionals on our user-friendly Q&A platform.

If f(x) varies directly with x, and f(x) = 18 when x = 2, find the value of f(x) when x = 6.

A.
6

B.
18

C.
36

D.
54


Sagot :

If f(x) varies directly with x, that mean there exists some unknown number k such that f(x) = kx.

So we were given that f(x) = 18 when x = 2. So plugging in these values will help you find the value of k.

18 = 2k

k = 9

So we know that k=9, therefore f(x) = 9x.

Now, at x=6, you have f(6) = 9·6 = 54

Therefore answer is D.