ANSWER
Explicit formula:
[tex]a_n= 8n - 23[/tex]
Recursive
[tex]a_{n}= a_{n - 1} + 8,a_1=-15[/tex]
EXPLANATION
The first term of the sequence is
[tex]a_1=-15[/tex]
The common difference is
[tex]d = - 7 - - 15[/tex]
[tex]d = 8[/tex]
The nth term is given by the formula,
[tex]a_n=a_1 + d(n - 1)[/tex]
[tex]a_n= - 15+ 8(n - 1)[/tex]
[tex]a_n= - 15+ 8n -8[/tex]
The explicit formula is;
[tex]a_n= 8n - 23[/tex]
The recursive definition is
[tex]a_{n}= a_{n - 1} + 8,a_1=-15[/tex]