Respuesta :

1) 3x
2) 3(x)
3) 3·x
4) 3*x
Hello, there! 

There's: 
↓↓
[tex]3*x \\ 3(x) \\ 3x \\ 3 of X[/tex]

Good luck on your assignment and enjoy your day! 

~[tex]MeIsKaitlyn:)[/tex]