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Math Help - Trigonometric Ratios

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    Senior Member vaironxxrd's Avatar
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    Trigonometric Ratios

    Hello Guys here its a Geometry homework i had, and i just want to check with you guys if i did this question right since is kind of confusing. First my answers and then the picture with the question just making sure i got the right answer here... I could not scan the steps.
    ---Rounded to the nearest thousand---
    D=5168FT

    X=1768FT

    (Image)



    Uploaded with ImageShack.us
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    A Plied Mathematician
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    Can you find the vertical drop?
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    Senior Member vaironxxrd's Avatar
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    Quote Originally Posted by Ackbeet View Post
    Can you find the vertical drop?
    They are listed above .

    "D=5168FT

    X=1768FT"

    BTW the book did not list these i found the vertical drop by first solving D which is the distance a person would travel at the slope.. Sorry for the lots of TYPOS
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    Hmm. Well, the vertical drop figure, at least, can't possibly be right. How did you get that answer?
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    Senior Member vaironxxrd's Avatar
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    Quote Originally Posted by Ackbeet View Post
    Hmm. Well, the vertical drop figure, at least, can't possibly be right. How did you get that answer?
    Took the Focus angle which was 20(Degrees),found out it was opposite over hypotenuse which is Sin
    So SIN(20)= \dfrac{x}{5168}
    Last edited by vaironxxrd; February 18th 2011 at 03:18 AM.
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    where did the number 5169 come from ?

    from the picture, x = 5500 - 5018 = 482 \, ft

    \sin(20^\circ) = \dfrac{x}{d}

    solve for d
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    You're going about this wrong. The value of \displaystyle X is KNOWN - it's \displaystyle 5500 - 5018 = \dots.

    You use THIS value to find \displaystyle D.
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    Senior Member vaironxxrd's Avatar
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    Quote Originally Posted by skeeter View Post
    where did the number 5169 come from ?

    from the picture, x = 5500 - 5018 = 482 \, ft

    \sin(20^\circ) = \dfrac{x}{d}

    solve for d
    Quote Originally Posted by Prove It View Post
    You're going about this wrong. The value of \displaystyle X is KNOWN - it's \displaystyle 5500 - 5018 = \dots.

    You use THIS value to find \displaystyle D.
    I will solve it from school. But why are we doing elevation-elevation or (5500)-(5018)
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    You start off 5018 ft above the ground and end up 5500 ft above the ground. How far have you travelled vertically?
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    Quote Originally Posted by vaironxxrd View Post
    Hello Guys here its a Geometry homework i had, and i just want to check with you guys if i did this question right since is kind of confusing. First my answers and then the picture with the question just making sure i got the right answer here... I could not scan the steps.
    ---Rounded to the nearest thousand---
    D=5168FT

    X=1768FT

    (Image)



    Uploaded with ImageShack.us
    You appear to have added 150 ft onto 5018 ft to get D.
    Why ?

    In your sketch, it states

    The vertical drop is the difference in the elevations
    Last edited by Archie Meade; February 18th 2011 at 06:08 AM.
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    Senior Member vaironxxrd's Avatar
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    Quote Originally Posted by Archie Meade View Post
    You appear to have added 150 ft onto 5018 ft to get D.
    Why ?

    In your sketch, it states

    The vertical drop is the difference in the elevations

    I actually Took the Focus angle which is 20(Degrees) and found out it was COS Because Adjacent over hypotenus. GOT [Math]\dfrac{COS20}{1}=[/tex] \dfrac{5500}{D}
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    Quote Originally Posted by vaironxxrd View Post
    I actually Took the Focus angle which is 20(Degrees) and found out it was COS Because Adjacent over hypotenus. GOT [Math]\dfrac{COS20}{1}=[/tex] \dfrac{5500}{D}
    Ok,

    You are incorrectly taking that elevation as being the length of the top horizontal blue line,
    (whose purpose mainly is to illustrate the angle of depression),
    whereas the elevation is "height above sea-level".

    (And if that was it's length, D would be longer)
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    Senior Member vaironxxrd's Avatar
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    Quote Originally Posted by Archie Meade View Post
    Ok,

    You are incorrectly taking that elevation as being the length of the top horizontal blue line,
    (whose purpose mainly is to illustrate the angle of depression),
    whereas the elevation is "height above sea-level".

    (And if that was it's length, D would be longer)
    I already fixed it but still I get 1409 ft for D
    For X I got 482ft
    Last edited by vaironxxrd; February 18th 2011 at 09:52 AM.
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    Quote Originally Posted by vaironxxrd View Post
    I already fixed it but still I get 1409 ft
    For X I got 482ft
    That seems fine for D
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    Senior Member vaironxxrd's Avatar
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    Quote Originally Posted by Archie Meade View Post
    That seems fine for D
    yea sorry i did not express it .. I was rushing through the steps i think that is why i get them wrong i usually rush
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