Answer:
= 1 + (n-1)84
Explanation:
to solve a sequence there's a formula-
+(n-1)d
where a1 is the first term, and d is the common difference
since we know the first term, and we have a few subsequent terms we can solve for d and creat the general formula for the nth term
to find d we simply check the difference between two terms-
168-x = 84
168-84 = x
84 = x
we can confirm this by checking the next two even
252- x = 168
252 - 168 = x
84 = x
now we have enough for a general formula
= 1 + (n-1)84