Question

Which answer is the explicit rule for the sequence: 10.5, 9, 7.5, 6, 4.5, 3, ...

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Answer 1

10.5 to 9 is -1.5 it continuously does this

Answer 2

10.5 +1.5 = ?

Answer 3

12.

Answer 4

you can cancel out two choices now, what are they?

Answer 5

yea its an arithmetic series with common difference (d) = -1.5

Answer 6

A and C could be crossed out.

Answer 7

correct

Answer 8

now the sequence is it subtracting or adding

Answer 9

the rule is nth term (an) = a1 + (n-1)d

where a1 = first term and d = common difference

Answer 10

Subtracting?

Answer 11

yes

Answer 12

so plugging in a1 = 10.5 and d = -1.5 into that formula will give you the answer

Finally simplify to get one of the options

Answer 13

I mean B.

Answer 14

10.5 -1.5(n - 1)

Simplify

Answer 15

= 10.5 - 1.5n + 1.5

Now add like terms and you have it.

Answer 16

It's B.

Answer 17

yes
10.5 + 1.5 = 12

so its
12 - 1.5n

Answer 18

Thank you both.

Answer 19

yw