The numbers of seats in the first 12 rows of a high-school auditorium form an arithmetic sequence. The first row has 9 seats. The second row has 11 seats.

a) Write a recursive formula to represent the sequence.
b) Write an explicit formula to represent the sequence.
c) How many seats are in the 12th row?

Question

The numbers of seats in the first 12 rows of a high-school auditorium form an arithmetic sequence. The first row has 9 seats. The second row has 11 seats. 

a) Write a recursive formula to represent the sequence. 
b) Write an explicit formula to represent the sequence. 
c) How many seats are in the 12th row?

anonymous · Answer

The 12th row would have 31 seats in it. Take the previous row and add two to get the next row. Not sure about how to write the formulas, sorry :)

anonymous · Answer

That's okay at least you tried lol.

anonymous · Answer

I was never taught about those type of formulas..they just told us to draw the pictures out lol