The sequence is arithmetic, so
Explicit formula is:
for a1 = 60 and d = -30
[tex]\begin{gathered} a(n)=60-30(n-1) \\ a(n)=60-30n+30 \\ a(n)=90-30n \end{gathered}[/tex]
Recursive formula is:
[tex]\begin{gathered} a(n)=a_{n-1}-30,\text{ for n>1} \\ a(1)=60 \end{gathered}[/tex]
