Answer:
[tex]f(x)=450-3x.[/tex]
Step-by-step explanation:
If Leon starts with 450 grams of tea leaves, and each morning he uses 3 grams of tea leaves, and if he uses this amount everyday then after [tex]x[/tex] days he will have used [tex]3x[/tex] grams of trees, and the grams of tea leaves [tex]f(x)[/tex] left will be
[tex]\boxed{f(x)=450-3x}[/tex]
This equation simply means that the amount of tea leaves left [tex]f(x)[/tex] after [tex]x[/tex] days is equal to the initial amount of leaves (450 grams) minus the amount used in [tex]x[/tex] days [tex](3x).[/tex]