an airplane travels 480 miles in 3 hours with the Wind. the return trip against the wind takes 4 hours. what is the wind speed and the speed of the airplane in still air?​

Respuesta :

Answer:

Plane speed: 100  &  Wind:20

Step-by-step explanation:

Plane speed =x mph

wind speed =y mph

against wind 6 hours

with wind 4 hours

Distance against 480 miles distance with 480 miles

t=d/r against wind -

480 / ( x - y )= 6

6 ( x - y ) = 480

6 x - 6 y = 480 ....................1

480 / ( x + y )= 4.00

4.00 ( x + y ) = 480

4.00 x + 4.00 y = 480 ...............2

Multiply (1) by 4

Multiply (2) by 6 24

we get

24.00 x + -24 y = 1920

24.00 x + 24 y = 2880

48 x = 4800

/ 48

x = 100 mph

plug value of x in (1)

6 x -6 y = 480

600 -6 y = 480

-6 y = 480 -600

-6 y = -120 mph

y = 20

Plane speed 100 mph

wind speed 20 mph