20% of the size of the side angle​

Me what is the value of x? showing work would be appreciated - ! : )

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.

The table represents a linear function. what is the slope of the function? –6 –4 4 6