Question

F(x) varies directly with x and
f(x) = 30 when x = 6. Find f(12).​

Answer 1

f(x)=30
x=6
We already have x.
So plug it into the equation:
f(6)=30

Although, we need to solve the first variable in the equation, then substitute the result into the equation.

Divide 30 by 6, which equals to 5.

Therefore, f equals 5.

I hope this helps you out!