a sub n= -11 +7n find a sub 34

Question

infinite algebra 2 solving arithmetic sequences

 

Answer 1

Actually, the way the question is stated above, it asks for the 34th term if the nth term is -11+7n. Thus the answer would be -11+7*34=227, As mentioned by Nicole.

Answer 2

Is it asking for the sum of the arithmetic sequence at 34? Or the value of the 34th term? Value: plug 34 in for n: -11 + 7(34) = 227 Sum for arithmetic: Sum at nth term = [2(a1) + d(n-1)](n/2) where n = 34 a1 = plug in 1 for n = -11 + 7(1) = -4 d = the difference between the numbers = 7 a1 = -4, a2 = -11 + 7(2) = 3 --- 3 - (-4) = 7 [2(-4) + 7(34-1)](34/2) = 3791