Lexi has $80 to spend on an ice cream treat each week. If she spends $4 on ice cream per week, the function C(x)=80−4x C ( x ) = 80  4 x represents how much ic
Mathematics
curry30k210536
Question
Lexi has $80 to spend on an ice cream treat each week. If she spends $4 on ice cream per week, the function C(x)=80−4x
C
(
x
)
=
80

4
x
represents how much ice cream money, C, Lexi has left after a certain number of weeks, x. What is the domain in the context of the problem? Why?
C
(
x
)
=
80

4
x
represents how much ice cream money, C, Lexi has left after a certain number of weeks, x. What is the domain in the context of the problem? Why?
1 Answer

1. User Answers sam4040
Answer:
Domain[tex]=\{1,2,3,4,5,6,7,8,9,10,11,12,,13,14,15,16,17,18,19,20\}[/tex]
In other words Domain[tex]=\{xx\ is\ an\ integer\ and\ 1\leq x\leq20\}[/tex]
Stepbystep explanation:
[tex]C(x)=804x[/tex]
Let after [tex]t[/tex] weeks she has left no money.
[tex]c(t)=0\\804t=0\\4t=80\\t=20[/tex]
That means she can have money for ice cream from the week 1 to week 20 and after that she will have no money.
So [tex]x[/tex] can be any number between [tex]1[/tex] and [tex]20[/tex]
Hence Domain[tex]=\{xx\ is\ an\ integer\ and\ 1\leq x\leq20\}[/tex]