Answer:
a(4) = -17
Step-by-step explanation:
hello :
use : a(n) =a(n-1) -5
a(n) -a(n-1) = -5 (common differnce for arithmetic sequence)
the ni-eme term is : a(n) = a(1) +(n-1)d d = -5 and a(1) = -2
so : a(n) = -2 +(n-1)(-5)
a(n) = -5n+3
when : n= 4 a(4) = -5(4)+3 =-17
