Tolong dibantu yha kak:v

2a.
[tex] 2a. \\ = 2(x) + 10 \\ = 2(30) + 10 \\ = 60 + 10 \\ = 70[/tex]
2b.
[tex] = 4(x) + 40 \\ = 4(20) + 40 \\ = 80 + 40 \\ = 120[/tex]
3a.
[tex] = 3(x) + 60 \\ = 3(20) + 60 \\ = 60 + 60 \\ = 120[/tex]
itu saja yg saya mampu :v maaf kalau salah :D