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Homework Help: Trig Problem

  1. Oct 4, 2004 #1
    Hello all:

    I am stuck on this problem:

    From a ship offshore, the angle of elevation of a hill is 1.1 degrees. After the ship moves inland at 4.5 knots for 20 min, the angle of elevation is 1.4 degrees. How high is the hill? (1 knor = i nautical mile per hour = 6080 feet approx)

    I first drew a horizontal line. I know 20 min is 1/3 of an hour, so the ship traveled 1.5 knots inland. Basically I have a right triangle consisting of two triangles with the two angle of elevations, and also know that the length of one of the sides of a triangle is 1.5. How would I solve for the height? Would I use the law of sines or cosines?

    Any help would be appreciated

  2. jcsd
  3. Oct 4, 2004 #2
    [tex]tan\ 1.1^0=\frac{x}{1.5+y}[/tex]
    [tex]tan\ 1.4^0=\frac{x}{y}[/tex]
    Solve for x.

    Attached Files:

    Last edited: Oct 4, 2004
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