I am having problems with the following problem that relates p(price) and demand (x) with the equation:

1. If the price is increasing at a rate of $ 2 per mo. when the price is $ 30; how do I find the rate of change of the demand?

I understand that I need to implicitly dif. but I'm not sure what to plug in after this step...

2. How do I find the rate of change of the price when demand is decreasing 6 units per mo when demand is 150?

Any help would be greatly appreciated