SOLUTION: Use two equations in two variables to solve the application. It takes a motorboat 4 hours to travel 56 miles down a river, and it takes 3 hours longer to make the return trip.

Algebra ->  Coordinate Systems and Linear Equations -> SOLUTION: Use two equations in two variables to solve the application. It takes a motorboat 4 hours to travel 56 miles down a river, and it takes 3 hours longer to make the return trip.       Log On


   

Question 1130788: Use two equations in two variables to solve the application.
It takes a motorboat 4 hours to travel 56 miles down a river, and it takes 3 hours longer to make the return trip. Find the speed of the current.
Answer by solver91311(24713) About Me  (Show Source):
You can put this solution on YOUR website!


Let represent the speed of the boat in still water.

Let represent the speed of the river current

The distance is a constant 56 miles. Time for the downstream (with the current) trip is 4 hours, time for the upstream (against the current) trip is 7 hours (4 + 3).

Rate of speed of the boat considering the current is downstream and upstream. Then since rate times time equals distance:





Solve the system for


John

My calculator said it, I believe it, that settles it