College algebra
posted by Anonymous .
A cyclist bikes at a constant speed for 18 miles. He then returns home at the same speed, but takes a different route. His return trip takes one hour longer and is 23 miles. Find his speed

let the speed be x mph
time for first trip = 18/x
time for 2nd trip = 23/x
23/x  18/x = 1
5/x = 1
x = 5
his speed is 5 mph
check:
time for 1st trip = 18/5 = 3.6 hrs
time for 2nd trip = 23/5 = 4.6 hrs, which is 1 hour more 
Let X be distance per hour,
Ist trip=18miles =18/X
2nd trip=23miles =23/X,=1hr longer
speed,S=2nd trip1st trip
X=2318
X=5mph.
checkings
23/5 18/5 =4.63.6=1hr