# Math Help - Related Rates!

1. ## Related Rates!

Suppose that the price p (in dollars) and the weekly sales x (in thousands of units) of a certain commodity satisfy the demand equation 2p^3 + x^2 = 4500.
Determine the rate at which sales are changing at a time when x = 50, p = 10, and the price is falling at the rate of \$0.50 per week. (Thanks in advance!)

2. Differentiate your equation, sub in what you are given and find dx/dt.

$6p^{2}\frac{dp}{dt}+2x\frac{dx}{dt}=0$