Question 810591
Aplane flying 3458-mi from new york city to london has a 50mph tailwind. The flights point of no return is the point at which the flight time required to return to new york is the same as the time required to continue to london. If the planes speed in still air is 860 mph, how far is new york from the point of no return?
The distance from new york to the point of no return is ____mi.


still air speed = 860 mph
wind speed = 50 mph

t=d/r

let x be the distance of point of no return from NY
distance from London = 3458-x

time to London d/r= 3458-x/(860+50)
=(3458-x)/910

time to NY  *against wind)
=x/(860-50)
=x/810

These times are same

(3458-x)/910=x/810

910x=810*(3458-x)

910x=2800980-810x

1720x=2800980
x=1628 

the distance of point of no return from NY= 1628 miles