Results 1 to 4 of 4

Math Help - Numbers representing sides of a triangle

  1. #1
    Junior Member
    Joined
    Sep 2008
    Posts
    71

    Numbers representing sides of a triangle

    Hello. I was wondering how do you find out how numbers can represent the lengths of the sides of a triangle that has a square root and just numbers.

    An example would be this one: 7, √5, 3√6. would this be an obtuse triangle?

    Also would anyone care to explain? Thanks.

    Is it a right, acute, or obtuse?
    Last edited by Jubbly; January 5th 2010 at 07:58 PM.
    Follow Math Help Forum on Facebook and Google+

  2. #2
    Junior Member
    Joined
    Jun 2009
    Posts
    61
    any three numbers can represent the sides of a triangle
    if you don't include conditions on the angles.
    Follow Math Help Forum on Facebook and Google+

  3. #3
    Newbie
    Joined
    Jan 2010
    Posts
    3
    using SSS we can figure out the name of any triangle, and with a bit of math, the exact angles

    say the numbers were 3 4 and 5 know that that triagle is a right triangle, and with a little math one could find it is 90 36.87 and 53.13
    Follow Math Help Forum on Facebook and Google+

  4. #4
    -1
    e^(i*pi)'s Avatar
    Joined
    Feb 2009
    From
    West Midlands, England
    Posts
    3,053
    Thanks
    1
    Quote Originally Posted by Jubbly View Post
    Hello. I was wondering how do you find out how numbers can represent the lengths of the sides of a triangle that has a square root and just numbers.

    An example would be this one: 7, √5, 3√6. would this be an obtuse triangle?

    Also would anyone care to explain? Thanks.

    Is it a right, acute, or obtuse?
    You can, but the explanation requires trig to find out.

    The cosine rule says that c^2=a^2+b^2-2abcosC and so

    cosC = \frac{a^2+b^2-c^2}{2ab}

    Where a, b, c are sides and A, B, C are angles opposite sides a,b,c respectively

    Law of cosines - Wikipedia, the free encyclopedia
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. sides of triangle
    Posted in the Trigonometry Forum
    Replies: 4
    Last Post: December 6th 2009, 11:11 AM
  2. Replies: 7
    Last Post: July 19th 2008, 07:53 AM
  3. sides of a triangle
    Posted in the Algebra Forum
    Replies: 3
    Last Post: May 16th 2008, 07:17 AM
  4. three sides of a triangle
    Posted in the Trigonometry Forum
    Replies: 1
    Last Post: April 1st 2008, 08:22 AM
  5. A triangle and its sides
    Posted in the Geometry Forum
    Replies: 2
    Last Post: September 9th 2005, 05:00 AM

Search Tags


/mathhelpforum @mathhelpforum