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Homework Help: Trig word prob

  1. Dec 28, 2004 #1
    Jennie stands 30 m from the base of a high rise building. The angle of elevation from her eyes to the top of the tower is 70°. How high is the tower if her eyes are 1.8 m above the ground?

    Is the answer to this 82.42 m + 1.8m=84.22 m?
  2. jcsd
  3. Dec 28, 2004 #2
    tan(70) = x/30 = 82.42

    82.42 + 1.8 = 84.22

  4. Dec 28, 2004 #3


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    Your first equation doensn't make any logical sense... :grumpy:
    [tex]\tan 70°=\frac{h}{30}\sim 2.747 \Rightarrow h\sim 2.747\cdot 30=82.415m [/tex]
    Total height:approx.84.2 m.


    PS.1.80m to her eyes,almost 1.90m in all:that's a giant *****...!! :tongue2:
  5. Dec 28, 2004 #4
    [tex]Tan \Psi = \frac {Opp}{Adj}[/tex]

    [tex]Tan 70 = \frac {x}{30}[/tex]

    [tex]x = Tan70 \times 30[/tex]

    [tex]x = 82.42[/tex]

    Then add 1.8m becaue of her eye level:

    [tex]y = 82.42 + 1.8[/tex]

    [tex]y = 84.22m[/tex]

    Therefore I say you are right in what you originally said.

    The Bob (2004 ©)

    P.S. Well my eye level is about 1.95m :tongue2:
  6. Jan 22, 2005 #5
    1.9 meters is not a giant...
    its about 6 feet 3 inches...
    im 6' exactly
  7. Jan 23, 2005 #6
    If you check my post above I said that my eye level was about 1.95m (probably more now :tongue2:) and I am not a giant. Just rather tall.

    The Bob (2004 ©)
  8. Jan 23, 2005 #7


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    Since i'm only 1.71,i feel quite uncomfortable when a lady next to me is towering 20 cm more...Bob,if u were near a girl at 2.15,u'd feel the same way... :tongue2:

  9. Jan 23, 2005 #8
    1.90 meters is very tall for a girl, too tall, in fact. I'd say that she's "deformed."
    Last edited: Jan 23, 2005
  10. Jan 23, 2005 #9
    I most likely would but you find a female 2.15m :tongue2:

    I have met a female almost as tall as me, two infact, and you do wonder why or how. Then you think why or how you are that tall as well.

    The Bob (2004 ©)
  11. Jan 23, 2005 #10
    A little harsh really.

    The Bob (2004 ©)
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