Question

Determine if the sequence is arithimetic if it is find the common difference and the explicit formula
1. -39, -48, -57, -66
A. Common difference : d=-11
Explicit : = -29-11n
B. Common difference :d=-9
Explicit an=-31-9n
C. Common difference : d=-7
Explicit an =-31-9n
D. Common difference : d=-9
Explicit an =-30-9n

Answer 1

@cwrw238

Answer 2

@101

Answer 3

Subtract again.

Answer 4

-39 -48 , -48--57 and -57--66?

Answer 5

@101

Answer 6

i got -9 sir @101

Answer 7

That is correct.

Answer 8

So which do you think it is, C or D ?

Answer 9

*B or C

Answer 10

B?

Answer 11

@101

Answer 12

No

Answer 13

C

Answer 14

how is it C

Answer 15

i mean D

Answer 16

@101

Answer 17

Yes

Answer 18

How is it D

Answer 19

-30 - 9^1 = -39

Answer 20

so is that how i find the explicit formula ?