Respuesta :

Answer:

[tex]a_{n}[/tex] = - [tex]\frac{1}{4}[/tex] [tex]a_{n-1}[/tex]

Step-by-step explanation:

The recursive formula lets us find a term in the sequence by multiplying the previous term by the common ratio r

Here r = [tex]\frac{20}{-80}[/tex] = [tex]\frac{-5}{20}[/tex] = - [tex]\frac{1}{4}[/tex]

Then recursive formula is

[tex]a_{n}[/tex] = - [tex]\frac{1}{4}[/tex] [tex]a_{n-1}[/tex]