Results 1 to 3 of 3

Math Help - Urgent help with geometry problem

  1. #1
    Newbie
    Joined
    Aug 2007
    Posts
    2

    Urgent help with geometry problem

    Hi, I'm new to the forum and I need help with this geometry problem.


    It is meant to be a layout of a car park constructed out of a normal hexagon and a normal rectangle. So all sides of the hexagon are 9m.

    I need to find the following:

    1.
    Find the perimeter. This one is simple enough.

    2.
    If A is the midpoint of DC, find the size of the angle y.

    3.
    Find the length of side x.

    4.
    Calculate the area of the triangle ABC.

    5.
    Calculate the area of the whole shape.

    I'm mostly just unsure of where to start and what methods to use. If anyone could show me how to work through these questions or point me in the right direction that would be greatly appreciated.

    Thanks in advance.

    EDIT: I guess this should probably have gone in the Trig forum.
    Last edited by Jahmez; August 9th 2007 at 12:28 AM. Reason: No reason
    Follow Math Help Forum on Facebook and Google+

  2. #2
    Super Member
    earboth's Avatar
    Joined
    Jan 2006
    From
    Germany
    Posts
    5,806
    Thanks
    116
    Quote Originally Posted by Jahmez View Post
    Hi, I'm new to the forum and I need help with this geometry problem.


    It is meant to be a layout of a car park constructed out of a normal hexagon and a normal rectangle. So all sides of the hexagon are 9m.

    I need to find the following:
    1.
    Find the perimeter. This one is simple enough.
    2.
    If A is the midpoint of DC, find the size of the angle y.
    3.
    Find the length of side x.
    4.
    Calculate the area of the triangle ABC.
    5.
    Calculate the area of the whole shape.

    I'm mostly just unsure of where to start and what methods to use. If anyone could show me how to work through these questions or point me in the right direction that would be greatly appreciated.

    Thanks in advance.

    EDIT: I guess this should probably have gone in the Trig forum.
    Hello,

    to # 2.:
    since the 2 trapezoids are the halves of a regular hexagon you get:
    AB = BC = AC = 9. That means triangle ABC is an equilateral triangle. Therefore the angle y = 60.

    to #3:
    x = AB = 9 m. See above.

    to #4.:
    If s is the side of an equilateral triangle it's area is calculated by:

    A_{eqi.~triangle} = \frac{1}{4} \cdot s^2 \cdot \sqrt{3}. Plug in the value you know (s = 9 m).

    A_{eqi.~triangle} = \frac{1}{4} \cdot 9^2 \cdot \sqrt{3} = \frac{81}{4} \cdot \sqrt{3}

    to #5.:

    The complete area consists of 6 triangles and 1 rectangle. Since AC = 9 m the width of the rectangle is 18 m. Thus the complete area is:

    A_{complete}=6 \cdot \frac{81}{4} \cdot \sqrt{3} + 18 \cdot 30= \frac{243}{2} \cdot \sqrt{3} + 540 \approx 750.444~m^2
    Follow Math Help Forum on Facebook and Google+

  3. #3
    Newbie
    Joined
    Aug 2007
    Posts
    2
    Thanks earboth
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. urgent-differential geometry
    Posted in the Differential Geometry Forum
    Replies: 4
    Last Post: January 21st 2010, 09:12 AM
  2. Urgent Geometry assistance?
    Posted in the Math Topics Forum
    Replies: 1
    Last Post: February 7th 2009, 06:33 AM
  3. Geometry - Urgent!
    Posted in the Geometry Forum
    Replies: 1
    Last Post: January 1st 2009, 03:57 AM
  4. Need urgent help in Geometry!
    Posted in the Geometry Forum
    Replies: 1
    Last Post: September 11th 2008, 03:28 PM
  5. urgent geometry prob.
    Posted in the Geometry Forum
    Replies: 2
    Last Post: May 9th 2007, 02:24 PM

Search Tags


/mathhelpforum @mathhelpforum