help with 3 math problems please i will upvote

1.)What is the common difference d of the sequence?

9, −8, −25, −42, −59, ...
Enter your answer in the box.
d =

2.)Which answer is the explicit rule for the sequence:
13, 10.5, 8, 5.5, 3, 0.5, ...

A. a n power =15.5−2.5n

B. a n power=15+2.5n

C. a n power=15.5+2.5n

D. a n power=15−2.5n

3.)Haylee has $440 in her savings account. She deposits $65 in her account every week.
How much money will Haylee have in her savings account after 25 weeks?



Respuesta :

1. common differece, d = a2 - a1d = -8 - 9 = -17d = -25 - (-8) = -17
2. first is solve the common differece,dd = 10.5 - 13 = -2.5so an = 15.5 - 2.5n is the answer
3. a(x) = 440 + 65xwhere x is the number of weeksa(25) = 440 + 65(25)a(25) = $2065