Respuesta :

a   = a   + d(n-1)

 n      1

this is the formula for the arithmetic sequence.

the first sequence is arithmetic

an=1+7(n-1)

the second sequence is also arithmetic

an=12+4(n-1)

Expression for nth Term:

a) 1 + 7(n-1)

b) 12 + 4(n-1)

Step-by-step explanation:

The formula for the nth Term of a Linear Sequence = a + i (n-1)

a = Starting number

i = Increment between patterns

n = The number of the Term that you seek