SOLUTION: Brendan and Andrew both leave the library at the same time, but in opposite directions. If Andrew travels 7 mph faster than Brendan and after 9 hours they are 207 miles apart, how

Algebra ->  Probability-and-statistics -> SOLUTION: Brendan and Andrew both leave the library at the same time, but in opposite directions. If Andrew travels 7 mph faster than Brendan and after 9 hours they are 207 miles apart, how       Log On


   

Question 1118110: Brendan and Andrew both leave the library at the same time, but in opposite directions. If Andrew travels 7 mph faster than Brendan and after 9 hours they are 207 miles apart, how fast is each traveling?
Answer by greenestamps(13200) About Me  (Show Source):
You can put this solution on YOUR website!


The sum of their speeds is the rate at which the distance between them is increasing; that rate is 207/9 = 23 mph. Then

let x = Brendan's speed
then x+7 = Andrew's speed
x + (x+7) = 23

Solve formally with basic algebra if required; or solve informally using logical reasoning.