Please help with this word problem!

Answer:
first blank: c(x) = 45x + 14
second blank: 7
Step-by-step explanation:
explanation for second blank:
set up the equation equal to 329:
45x + 14 = 329
subtract 14 from both sides:
45x = 315
divide by 45 to leave x alone:
x = 7
Shaun will be able to rent the car for 7 days.