Find the common difference and recursive formula

3)

The first term is 35 and it keeps getting subtracted by 30 to get the other terms so this is the common difference, so we can write:

[tex]\sf a_n = a_{n-1}-30[/tex]
[tex]\sf a_1=35[/tex]

4)

The first term is 5 and it keeps getting subtracted by 8 to get the other terms so this is the common difference, so we can write:

[tex]\sf a_n = a_{n-1}-8[/tex]
[tex]\sf a_1=5[/tex]

5)

The first term is -29 and it keeps getting added by 200 to get the other terms so this is the common difference, so we can write:

[tex]\sf a_n = a_{n-1}+200[/tex]
[tex]\sf a_1=-29[/tex]

6)

The first term is 11 and it keeps getting added by 100 to get the other terms so this is the common difference, so we can write:

[tex]\sf a_n = a_{n-1}+100[/tex]
[tex]\sf a_1=11[/tex]

7)

The first term is 37 and it keeps getting added by 30 to get the other terms so this is the common difference, so we can write:

[tex]\sf a_n = a_{n-1}+30[/tex]
[tex]\sf a_1=37[/tex]

8)

The first term is 20 and it keeps getting subtracted by 6 to get the other terms so this is the common difference, so we can write:

[tex]\sf a_n = a_{n-1}-6[/tex]
[tex]\sf a_1=20[/tex]