I'm completely lost, i need solving this

Need this asap if anyone can i would be very grateful. if you could show workings that would really

Tom wants to order tickets online so that he and three of his friends can go to a water park the cost of the tickets is 16.00 per person there is also a 2.50 one-time service fee for ordering tickets online write an expression in term of n that represents the cost for n ordering tickets online

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)