1) We can gather the data that way:
1st city
Hotel Charge before tax: x
tax rate: 5.5%
2nd city
Hotel charge before tax: (x-500)
Tax rate: 9.5%
Hotel tax 1st city + Hotel tax 2nd city = 665
2) Considering that to find the final cost we need to multiply the tax rate by the hotel charge, we can write out the following expression:
Now, let's plug into each expression to find the answer: