Answer: Choice C. an = 8 + 9(n-1)
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Work Shown:
a1 = 8 is the first term
a7 = 62 is the seventh term
an = a1+d(n-1) = nth term of arithmetic sequence
a7 = a1+d(7-1) ... plug in n = 7; solve for d
62 = 8+d(6)
62 = 6d+8
6d+8 = 62
6d = 62-8
6d = 54
d = 54/6
d = 9 is the common difference
an = a1 + d(n-1)
an = 8 + 9(n-1) is the nth term of this arithmetic sequence