We have the next function
c=cost
t= number of tickets
[tex]c=25t[/tex]
and you have the constrain that you can buy up 5 tickets
Domain
[tex]\mleft\lbrace0,1,2,3,4,5\mright\rbrace[/tex]
Range
[tex]\mleft\lbrace0,25,50,75,100,125\mright\rbrace[/tex]
As we can see the domain is discrete because you can not buy for example half of the ticket we only buy integers.
