Answer:
see explanation
Step-by-step explanation:
Substitute n = 7 into f(n)
f(7) = 5 + 8(7 - 1) = 5 + 8(6) = 5 + 48 = 53
f(n) = 5 + 8(n - 1) represents the nth term of an arithmetic sequence
f(n) = a₁ + (n - 1)d
where a₁ is the first term and d the common difference
By comparison, then
a₁ = 5 and common difference d = 8
