Let h be the set of integers less than or equal to eleven

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.

Need solving this second acceleration problem.

Angles r and s are complementary. the measure of angle r is 31 degrees. which equation can be used to find angle s?