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Trigonemtetric Word Problem

  1. Apr 5, 2006 #1
    "A plane is observed approaching your home and you assume its speed is 550 miles per hour...The angle of elevation of the plane is 16 degrees at one time and 57 degrees one minute later. Approximate the altitude of the plane."

    Ok I tried drawing triangles for this but I keep getting to a part where one side = 9.166 + unknown because I put the speed into miles per minute to find how much distance it covered in one minute I really can't figure out how to draw the triangle for htis problem I'm really confused about this can anyone help me clear it up the answer is 17054 feet or 3.23 but if anyone oculd give me an explanation of how to do this I would really appreciate it.
  2. jcsd
  3. Apr 5, 2006 #2
    Hints on drawing the triangle...
    (1) Draw a horizontal line on your paper representing ground level. Since you are watching the plane from the ground, all the angles of elevation will be with respect to this line.
    (2) Mark a point on the horizontal line, letting it represent your position.
    (3) Mark a point above the horizontal line (but not directly above you!), letting it represent the plane's initial position. If you join the 2 points, what can you say about the angle between the line formed and the horizontal?
    (4) Mark another point above the horizontal line, letting it represent the plane's position a minute later. Since we assume the plane's altitude does not change, what can we say about the line joining the 2 points which are above the horizontal?

    General hints:
    The plane has not passed you.
    Putting the plane's speed into miles per minute to find how much distance it covered in one minute is a step in the correct direction, as it will help you calculate the length of one of the sides of the triangle.
    Last edited: Apr 5, 2006
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