algebra 1, two variables

Question

A theater group made appearances in two cities. The hotel charge before tax in the second city was $500

 higher than in the first. The tax in the first city was 6.5%, and the tax in the second city was 7%. The total hotel tax paid for the two cities was $642.50. How much was the hotel charge in each city before tax? 

i don't understand how to convert this into math "language"

Answer 1

Let x = the hotel charge before tax in the first city

Let x + 500 = the hotel charge before tax in the second city

.065x + .07(x + 500) = 642.50

.065x + .07x + 35 = 642.50

.135x = 607.50

x = $4500

x + 500 = $5000