Write an equation that expresses the following relationship. U varies directly with the cube of P and inversely with D. In your equation,use

K as the constant of proportionality.

The equation that expresses the relationship described is:

U = K * (P^3) / D

In this equation, U is the variable that varies directly with the cube of P (P^3) and inversely with D. K represents the constant of proportionality.

To express the relationship between U, P, and D, we can use the equation:

U = K * (P^3) / D

Here:

- U represents the variable that varies directly with the cube of P and inversely with D.
- P represents the variable that is cubed.
- D represents the variable that U is inversely proportional to.
- K is the constant of proportionality.

Using this equation, as P increases, U will increase cubically, and as D increases, U will decrease inversely. K represents the scaling factor that determines the exact relationship between the variables.

u = kp^3/d