Answer:
f(x) = 0.5x
Explanation:
For this problem, we simply have to find the constant of proportionality between x and f(x). In other words, what x is multiplied by to get f(x).
Since this proportion is constant (meaning it doesn't change), all we have to do is divide an f(x) value in the table by its corresponding x value.
p = f(x) / x
p = -2 / -4
p = 1/2 = 0.5
We can show the relationship of x to f(x) with the equation f(x) = px, which can be simplified using the constant of proportionality that we just solved for.
f(x) = 0.5x