Question 185692: Solving Problems Using Linear Systems
8. With a tailwind, a plane flew the 3000 km from Calgary to Montreal in 5 h. The return flight, against the wind, took 6 h. Find the wind speed and the speed of the plane.
(The answer is: wind speed 50 km/h, speed of plane 550 km/h, but i dont know how to solve this question?) Thankssss!!!
Answer by ankor@dixie-net.com(22740)   (Show Source):
You can put this solution on YOUR website! 8. With a tailwind, a plane flew the 3000 km from Calgary to Montreal in 5 h.
0n The return flight, against the wind, took 6 h.
Find the wind speed and the speed of the plane.
:
Let x = speed of the plane in still air
Let y = speed of the wind
:
(x+y) = speed with the wind
(x-y) = speed against the wind
:
Write a distance equation for each trip: Dist = time * speed
:
5(x+y) = 3000
6(x-y) = 3000
:
Simplify, divide equation by 5 and divide equation 2 by 6, results:
x + y = 600
x - y = 500
--------------adding eliminates y, find x
2x = 1100
x = 
x = 550 km/hr is the speed of the plane in still air
then
550 + y = 600
y = 600 - 550
y = 50 km/hr is the speed of the wind
:
;
You can check the solutions in the 1st or 2nd original equation
|
|
|
