1) [tex]36x-9[/tex]. You can factor 9 from both terms and you get [tex]9(4x-1)[/tex]
2) [tex]36x+8[/tex]. You can rewrite 36 as 9*4 and 8 as 4*2, so you end in the last box
3) [tex]4(9x+2)[/tex]. If you expand this expression, you have 36x+8, so you are in the same case as (2)
4) [tex]9(4x+1)[/tex]. If you distribute the 9, you have 36x+9, so you end in the first box
5) Evaluate both multiplications: 9*4x=36x, 9*1=9. So, you have 36x+9, and again you end in the first box
6) Similarly, you have 3*12=36 and 3*3=9. So, the final result is again 36x+9.
