Answer:
Explicit form, f(n) = x +4n
Step-by-step explanation:
Here the sequence is given as x + 4, x + 8, x + 12, x + 16, ...
First term, f = x + 4
Common difference, d = x + 8 - (x+4) = 4
We have equation for nth term of arithmetic sequence as
[tex]f(n)=a+(n-1)d\\\\f(n)=x+4+(n-1)4=x+4+4n-4=x+4n\\\\f(n)=x+4n[/tex]
Explicit form, f(n) = x +4n