Let
c--------> the total cost
x------> the number of tickets
z------> the cost of one ticket without service fee
we know that
[tex]108=5.50+5z[/tex]
solve for z
combine like terms
[tex]5z=108-5.50[/tex]
[tex]5z=102.50[/tex]
[tex]z=\$20.50[/tex]
The linear function is equal to
[tex]c=5.50+20.50x[/tex]
therefore
the answer is
[tex]c=5.50+20.50x[/tex]
