Part (a)
This sequence is arithmetic because we are adding 4 to each term to get the next term. Nice work on getting the correct answer here.
To get the nth term of an arithmetic sequence, we'll use the formula below
an = a + d(n-1)
In this case, a = 14 is the first term and d = 4 is the common difference
So we have these steps
an = a + d(n-1)
an = 14 + 4(n-1)
an = 14 + 4n - 4
an = 4n + 10
Answer: 4n + 10
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Part (b)
This sequence is geometric since we multiply each term by 4
The common ratio is r = 4 and the start term is a = 2.
So the nth term is....
an = a*(r)^(n-1)
an = 2*(4)^(n-1)
Answer: 2*(4)^(n-1)
