Question

Tell whether the sequence is arithmetic. If it is, what is the common difference? (1 point)

Answer 1

Since an arithmetic sequence is a sequence of numbers and the difference of any two successive members of the sequence is a constant

So this question is arithmetic because it keep minus by 7

from 19 - 7 = 12

12 - 7 = 5

5 - 7 = -2

so common difference is -7

or you can check with arithmetic formular as

`a_(n)` =
`a_(1)` + (n−1)d

I will just put in the 4th term which is -2 and n will equal to 4

and
`a_(1)` is the 1st term which is 19

-2 = 19 + (4−1)d

-2 - 19 = 3d

d =
`(-21)/(3)`

d = -7