In a city, the distance between the library and the police station is 3 miles less than twice the distance between the police station and the fire station. The distance between the library and the police station is 5 miles. How far apart are the police station and the fire station?
x = distance between library and police station
y = distance between police station and fire station
x = 5
x = 2y - 3
5 = 2y - 3
5 + 3 = 2y
8 = 2y
8/2 = y
4 = y <=== distance between police station and fire station is 4 miles