Every input(x) has only one output(y)
Emily and Marie can’t have the same birthday in this so it’s not a function
This is a word problem signifying an algebraic expression.
Translating this to mathematics:

add 4 to both sides.
divide 16 to both sides.
this is:
Answer:
$19
Step-by-step explanation:
11+8 because every hour is =4 dollars and he was there for two hours which gave him 8 so 11+8=19 Jordan has to pay 19 dollars