The profit of a cell-phone manufacturer is found by the function , where x is the cost of the cell phone. At what price should the manufacturer sell the phone to maximize its profits? What will the maximum profit be?

Find the slope and the y-intercept if there's one and the equation of the line given these two points( 3, 2) and( 3, -4)

If f(x) = 3x2 - 2x+4 and g(x) = 5x + 6x - 8, find (f-g)(x).

Talia took the bus from her home to the bank and then walked back to her home along the same route. the bus traveled at an average speed of 40 km/h and she walked at an average speed of 5 km/h. to determine the time, x, that it took talia to walk home, she used the equation 40(0.9 – x) = 5x. the time of trip 2 is hours. the distance of trip 1 is km.