Answer:
Hooke's law can be written as:
F = -k*Δx
Where k is a constant that depends on the spring, called the spring constant.
And Δx = (x - x₀) is the displacement of the spring with respect to the rest position x₀
And a proportional equation is something like:
y = c*x
Where c is a constant of proportionality.
In the case of Hooke's law, the constant is K, then the force is proportional to the displacement of the spring with respect to the rest position Δx.