If BC = 5, and CD = 20, what is the exact value of AB?

Can someone me with my hwplz(only the circled ones)

Question 101 points)which equation in slope-intercept form represents the line that passes through (5, 1) and(-4,7)

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