Please help with this motion application. Thank you in advance! having trouble with this one!?

Here s a motion application problem:
Two cars are driving on opposite lanes of the freeway. Two and a half hours after they meet, they are 355 miles apart. If one car is traveling 6 miles per hour faster than the other, find the speed of each car.

Do the following for this problem:
a) assign variable expressions for each of the two unknowns
b) give an equation for the situation
c) solve the equation and answer the question in a complete sentence

Puzzling2019-03-11T06:17:59Z

Let s be the speed of the slower car (in mph)
Let s + 6 be the speed of the faster car (in mph)

After 2.5 hours, the first car has traveled a distance of:
2.5s
And the second car has traveled a distance of:
2.5(s + 6)

Together that's a distance of 355 miles:
2.5s + 2.5(s + 6) = 355
5s + 15 = 355
5s = 340
s = 340/5
s = 68

Answer:
The slower car is traveling 68 mph. The faster car is traveling 74 mph.

?2019-03-11T05:32:19Z

a) v and (v-6) mph
b) 2.5(2v-6) = 355
c) 2v-6 = 142
v = 74 mph
Speeds are 74 mph and 68 mph