PART B: Uber was also available for Mike to use to get home from the airport. Uber does not have an initial fee; it charges $3.45 per mile. Which would be a better deal the taxi or Uber for Mike's trip home?

Suppose that the price p, in dollars, and the number of sales, x, of a certain item follow the equation 4 p plus 4 x plus 2 pxequals56. suppose also that p and x are both functions of time, measured in days. find the rate at which x is changing when xequals2, pequals6, and startfraction dp over dt endfraction equals1.5.