Solve 5x²-2x-25=0 using completing the square method​

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 graphs could represent a quartic function?

Which graph shows the solution set of x^2+4-12x/> 0