Answer:
[tex]A. \: \boxed{ 5c - 5 = 45 }[/tex]
Step-by-step explanation:
[tex]let \: the \: cost \: of \: thier \: meal \: be \: \to \: c \\ then \to \\ the \: five \: of \: them \: will \: cost \: 5c \\ assuming \: he \: also \: ordered : it \: would \: had \: \\ been \: 5c = 45 \\ \boxed{but \: no}\\ since \: he \: did \: not \: oder \: but \: eat \: the \: rest \: \\ of \: the \: meal \to \\ the \: equation \: is \: givn \: by \to \\ \boxed{ 5c - 5 = 45}[/tex]