The first row of a concert hall has 25 seats and each row after the first has one more seat than the row before it. There are 2 rows of seat. 1)Write a rule for the number of seats in the nth row.

2)35 students from a class want to sit in the same row. How close to the front can they sit?

The statement, "There are 2 rows of seat" , is confusing.

Is there a front row of 25, then an aisle, and another 25 seats for the entire first row ???

Please be more specific.
Once that is cleared it looks like a simple arithmetic sequence question
with
a = 25
d = 1

Thanks! I knew it was row 11 but didn't know how to write a formula to prove it...

1) To find the rule for the number of seats in the nth row, we need to observe the pattern in the given information. We know that the first row has 25 seats. Each subsequent row has one more seat than the row before it. So, we can create the following pattern:

1st row = 25 seats
2nd row = 25 + 1 seat
3rd row = 25 + 1 + 1 seat
...
nth row = 25 + (n-1) seats

Therefore, the rule for the number of seats in the nth row is:
Number of seats in the nth row = 25 + (n-1)

2) If there are 35 students from the class who want to sit in the same row, we need to find the row which can accommodate at least 35 seats. We can use the rule found in step 1 to solve this problem.

We need to find the value of n for which the number of seats in the nth row is greater than or equal to 35. Setting up the inequality:

25 + (n-1) ≥ 35

Now, we can solve for n:

25 + n - 1 ≥ 35
n ≥ 35 - 25 + 1
n ≥ 11 + 1
n ≥ 12

Therefore, the students can sit in the row number 12 or any row after that to accommodate at least 35 students.

Now it is very easy

tn = a+(n-1)d
= 25 + (n-1)(1)
= 24 + n

so which row comes closest to 35 ?
24+n=n35
n=11

The 35 students can sit all in row 11

Sorry...there are 32 rows of seats