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What is the explicit rule for the sequence?

10.5, 9, 7.5, 6, 4.5, 3, ...




an=12−1.5n

an=12.5−1.5n

an=11−1.5n

an=12+1.5n

1 Answer

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Answer:

an=12−1.5n

Explanation:

The first term is 10.5.

The common difference is ...

9 - 10.5 = -1.5

The n-th term can be described by ...

an = a1 +d(n -1)

an = 10.5 -1.5(n -1) = 10.5 -1.5n +1.5 . . . . eliminate parentheses

an = 12 -1.5n

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