term(n) = a + (n-1)d
428 = 4 + (n-1)(8)
424 = 8n - 8
432 = 8n
n = 54
Draw your conclusion
in an arithmetic sequence a1=4 and d=8 which term is 428
Show your work
2 answers
S8 = 8/2 [2(A1) + (8 - 1)3]
172 = 8/2 [2A1 + (7)3]
172 = 8/2 (2A1 + 21)
344 = 8 (2A1 + 21)
344 = 16A1 + 168
344 - 168 = 16A1
11 = A1
172 = 8/2 [2A1 + (7)3]
172 = 8/2 (2A1 + 21)
344 = 8 (2A1 + 21)
344 = 16A1 + 168
344 - 168 = 16A1
11 = A1