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Homework Help: Trigonometry problems for NYSE regents

  1. Jul 24, 2010 #1
    1. The problem statement, all variables and given/known data

    In the diagram below, KW = 6, Kt = 5 and m<KTW = 90. What is the measure of angle K, to the nearest minute? Below is the website for this question because this is one of the questions from the algebra 2 and trigonomentary. This is question 23.

    http://www.nysedregents.org/a2trig/20100615exam.pdf [Broken]

    2. Relevant equations


    3. The attempt at a solution

    I know if you use the inverse of cosine in this problem you can get the degrees of K. For ex, cos (inverse) (5/6) = 33 degrees but I'm confused on how to get the minutes.
    Last edited by a moderator: May 4, 2017
  2. jcsd
  3. Jul 24, 2010 #2


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    Homework Helper

    Re: Trig

    You need to obtain more accuracy from the value of [tex]cos^{-1}(5/6)[/tex]

    Your calculator display should give something like 33.55730976 if set to degrees. A minute (denoted by ') is defined as being 1/60 of a degree, so 33o30' is the same as 33.5o because 30 is half of 60.


    Your calculator should have a button that can convert decimals to minutes and seconds (a second is a 60th of a minute - thinking of degrees as being hours should make it easily memorable), but if you can't find this button, it can quickly be done with a bit of thinking.

    We have 33.55730976 and we need to convert this into the form 33ox' to the nearest x. So all we have to deal with is the 0.55730976. Since a minute is 1/60 of a whole, then we have x/60=0.55730976. Now you have your minutes after you round off :smile:
  4. Jul 24, 2010 #3
    Re: Trig

    Thanks a lot. have a good day :)
  5. Jul 24, 2010 #4


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    Homework Helper

    Re: Trig

    You too priscilla :smile:
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