Answer:
[tex]a_{n}[/tex] = 5[tex](-2)^{n-1}[/tex]
Step-by-step explanation:
The recursive rule for a geometric sequence is
[tex]a_{n}[/tex] = a[tex](r)^{n-1}[/tex]
where a is the first term and r the common ration
Here
r = - 10 ÷ 5 = 20 ÷ - 10 = - 2 and a = 5, thus
[tex]a_{n}[/tex] = 5[tex](-2)^{n-1}[/tex]
