Nadia walks at an average speed of (x + 2) km/h for (x – 3) hours and cycles at an average speed of (3x + 5) km/h for x hours. She covers a total distance of 74 km. (i) Form an equation in x and show that it reduces to 4x2 + 4x - 80 = 0. (ii) Solve the equation 4x2 + 4x – 80 = 0. (iii) Find the time taken for her entire journey.