Final answer:
The rule for the given sequence is f(n) = 2.8 - 0.6(n - 1), which simplifies to f(n) = 3.4 - 0.6n.
Step-by-step explanation:
The sequence given is 2.8, 2.2, 1.6, and 1. To find the rule for this sequence, we can notice that each term decreases by 0.6 from the previous term. Beginning with the first term 2.8, if we subtract 0.6 once, we get 2.2; subtract twice, we get 1.6; subtract three times, we get 1.0, and so on. Thus, we can describe the nth term of the sequence with an equation by subtracting 0.6 from the initial term 2.8, n-1 times. The correct rule for this sequence is f(n) = 2.8 - 0.6(n - 1), which simplifies to f(n) = 3.4 - 0.6n. Option a) is the correct choice as it perfectly matches this rule when considering x as the nth term (not accounting for the typo).