An airplane flies into the wind for 5 hours, traveling 900 miles. The airplane then
turns around and flies with the wind, returning to its starting place in 4 hours.
This can be modeled by the following system of equations, where (s) is the speed
of the plane with no wind and (w) is the speed of the wind.
5(s-w)=900
4(s+w) = 900
What is the speed of the wind in miles per hour?