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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.

Which of the following is the best first step in solving the equation below? 4+2㏒³x=17

Identify the initial amount a and the growth factor b in the exponential function. a(x)=680*4.3^x