The function f(x) varies inversely with x and f(x) = 4 when x = 12. what is f(x) when x = 3? a. 1 b. 9 c. 16 d. 19

Step-by-step explanation:

We are given inverse relation between f(x) and x.

The function f(x) varies inversely with x.

Inverse relation could be written as

f(x) = .

We also given f(x) = 4 when x = 12.

Plugging f(x) = 4 and x=12 in the above inverse relation to get the value of constant k.

.

On cross multiplying, we get

12× 4 =

48 = k

Now, we need to find f(x) for x=3.

Plugging k=48 and x=3 in inverse relation, we get

.

an

y = 6x -3y -12

y +3y +12 = 6x

=> . x = { 2y / 3 +2 } this is equation of line in terms of x

=> . if line meets the x-axis the co-ordinates of meeting point would be ( x , 0 )

=> . x = 2 ( 0 ) / 3 + 2

=> . x = 2

so, the point is ( 2 , 0 )