The trains are going in opposite directions, one at 60 mph and the other at 50 mph. We can use this information to create the following formula, where variable "h" represents the number of hours:
50h + 60h = 550
Combine like terms:
110h = 550
Divide both sides by 110:
h = 5
We have now proven that it would take 5 hours for the two trains to be 550 mile apart.
Lets t be the time that needed for trains to be 550 mi apart. 1st train will go (60*t) mi 2nd train will go (50 *t) mi Altogether (60t +50t), at the same time this distance equals 550 mi. So, we can write 60t +50t =550 110t = 550 t=550/110 t=5 h
So we start by combining like terms; Now we have; We then subtract 1 from both sides; Then we divide both sides by 5; Leaving the final answer to be h = -2