Question

HELLP!

The function f(x) varies directly with x and f(x)=160 when x=40. What is f(x) when x=8 A)32 B)20 C) 5 D)2

Answer 1

The answer is (A) which is 32.. If u can f(x) =160 when x=40 and if we divide 160 by 40 we get 4.. Therefore we can say that to get the f(x) we have to multiple the value of x by 4. . *NB: as the value of x=40, f(x) is: 40×4=160 . * Therefore as the value of x=8, f(x) is: 8×4=32

Answer 2

Answer: Value of f(x)=32 when the value of x=8

Explanation:

Since we have given that

the function f(x) varies directly with x and f(x).

If x=40, f(x)=40

So, if x=8 then we have to find the value of f(x):

Since there is direct variation,

`(160)/(40)=(f(x))/(8)\\\\4=(f(x))/(8)\\\\4* 8=f(x)\\\\32=f(x)`

So, value of f(x)=32 when the value of x=8.