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Homework Help: Trig HELP Please

  1. Apr 17, 2008 #1
    Trig HELP Please!!

    I have a test tomorrow please help. I need to know how to do them like I tired them but I want to know if I am right so if you could help me find the equations for each that would be great!! Thanks

    1) A man stands on level ground 200 meters from the base of a TV tower. He finds he must look up at an angle of 26 degrees to see the top of the tower. How high is the tower?
    2) A kite flies at a height of 60 ft when 130 ft of string is out. Assuming that the string is in a straight line, what is the angle that the string makes with the ground?
    3) A man stands 120 meters from a tree, and finds that the angle of elevation to the top of the tree is 32.3 degrees. What is the height of the treee?
    4) An oil slick to the shore is observed from a lighthouse platform 200ft above sea level. The angle of depression to the near side of the slick is 39 degrees and to the far side is 28 degrees. How wide is the slick?
    5) A man standing on top of a building 35 meters high measures the angle of elevation of the top of the building across the street to be 32 degrees. He measures the angle of depression of the base of the same building to be 55 degrees. How far way is the building across the street AND how tall is it?
  2. jcsd
  3. Apr 17, 2008 #2
    Post what you've tried.
  4. Apr 17, 2008 #3
    Try to draw a triangle, mark its sides and hypothenuse,and the angle of elevation, and the others and see if you can come up with a trig identiy, or whatever, that relates the knowns and unknown data.
  5. Apr 17, 2008 #4
    1)equation:200tan26 degrees
    answer: 97.5 meters
    2) equation: angle=arcsin(60/130)
    answer: 27.5 degrees
    3) equation: height=120tan32.3
    answer: 75.86 meters
    4)equation: width=200tan39-200tan28
    answer:55.6 degrees
    5) equation: 35tan35
    answer 24.5 degrees
    I did not get the second answer and equation to #5 I do no know how to do it
    Are these equations and answers right for all of them?
  6. Apr 17, 2008 #5


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    Staff Emeritus
    Science Advisor
    Gold Member

    All of the above are correct, but be careful with the units!
    For question five, you need to construct a system of simultaneous equations. You have two unknowns (height and distance), therefore you need two equations.
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