Find an equation for the nth term of the arithmetic sequence.

a19 = - 92, a20 = 6

Choices:

an = - 1856 + 98 (n - 1)

an = - 1856 - 98 (n - 1)

an = - 1856 - 98 (n + 1)

an = - 1856 + 98 (n + 1)

A19 = - 92

a20 = 6

common difference = d = a20 - a19

d = 6 - (-92)

d = 6 + 92

d = 98

formula for nth term

an = a1 + (n-1) d

put n = 20

a20 = a1 + (20-1) d

6 = a1 + 19 (98)

6 = a1 + 1862

6 - 1862 = a1

-1856 = a1

a1 = - 1856

now nth term:

an = a1 + (n-1) d

an = - 1856 + (n-1) 98

an = - 1856 + 98 (n-1)