Please anyone help me I’ll brainlist you or whatvever and give you 20 points

Suppose that the price p (in dollars) and the weekly sales x (in thousands of units) of a certain commodity satisfy the demand equation 4p cubedplusx squaredequals38 comma 400. determine the rate at which sales are changing at a time when xequals80, pequals20, and the price is falling at the rate of $.20 per week.

Its worth 10000000 points need asap if you answer correctly ill mark brainliest

What is the effect on the graph of the function f(x)=x when f(x) is replaced with -f(x)+4