Precalculus 11

posted by Kayla

Hello,

An airplane makes a 990 km flight with a tailwind & returns, flying into the same wind. The total flying time is 3 hrs 20 mins & the airplanes speed in still air is 600 km/hr what is the the speed of the wind?

I'm as far as (990/(600-x))+(990/600+x))=10/3

but I can't figure out how to go from there!

Thanks a bunch :)
Kayla

  1. bobpursley

    same distance, there and back
    v1*t1=v2*t2=990km
    t1=3 1/3 hr -t2

    v1=600+w
    v2=600-w

    (600+w)t1=990 or
    t1=990/(600+w)
    10/3-t1=990/(600-w)

    10/3-990/(600+w) = 990/(600-w) so your equation is correct.

    now, multipy each side by (600-w)(600+w)/990

    10(600^2-w^2)/(3*990) = 600+w+600-w)
    check that. Now is simplifies considerably, gather terms, and you have a quadratic equation. use the quadratic formula.

  2. scott

    multiply by the LCD

    [990 (600 + x)] + [990 (600 - x)] = 10/3 (600 - x)(600 + x)

    1188000 = 10/3 (360000 - x^2) ... 356400 = 360000 - x^2

    x^2 = 3600

Respond to this Question

First Name

Your Answer

Similar Questions

  1. algebra-word problem

    Flying to Kampala with a tailwind a plane averaged 158 km/h. On the return trip the plane only averaged 112 km/h while flying back into the same wind. Find the speed of the wind and the speed of the plane in still air. TIA
  2. math

    a small plane flying into the wind takes 3 hrs 20 min to complete a flight of 960 km. Flying with the wind the same plane takes 2 h 30 min to make the trip.what is the speed of the plane?
  3. Algebra

    Flying with wind, a plane flew 800 miles in 5 hrs. Flying against the wind, the plane flew the same distance in 8 hrs. Find the still air speed and wind speed.
  4. math

    If you are flying to a city 800 miles away, what will be the difference in flight times between flying into a 40-mph headwind and flying with a 40-mph tailwind if the plane's maximum speed with no wind is 160 mph?
  5. math

    If you are flying to a city 800 miles away, what will be the difference in flight times between flying into a 40-mph headwind and flying with a 40-mph tailwind if the plane's maximum speed with no wind is 160 mph?
  6. Math Ms. Sue please help

    Flying to Kampala with a tailwind a plane average 158km/h. On the return trip the plane only averaged 112km/h while flying back into the same wind. Find the speed of the wind and the speed of the plane in still air.
  7. math

    Flying to Seoul with a tailwind a plane averaged 343 mph. On the return trip the plane only averaged 307 mph while flying back into the same wind. Find the speed of the plane in still air and the speed of the wind.
  8. Algebra

    A pilot flew a 400-mile flight in 2.5 hours flying into the wind. Flying the same rate and with the same wind speed, the return trip took only 2 hours, with a tailwind. What was the speed of the wind?
  9. Math

    If you are flying to a city 400 miles away, what will be the difference in flight times between flying into a 40-mph headwind and flying with a 40-mph tailwind if the plane's maximum speed with no wind is 160 mph?
  10. Math

    Have you ever been on an airplane and heard the pilot say that the plane would be a little late because it would be flying into a strong headwind or that even though the plane was taking off a bit late, you would be making up time …

More Similar Questions