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Thread: Maths question

  1. #1
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    Maths question

    OK all you engineers & maths students:
    What is the angle sum of a pentagon?
    What is the formula to work this out?

  2. #2
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    Re: Maths question

    Quote Originally Posted by vaughan
    OK all you engineers & maths students:
    What is the angle sum of a pentagon?
    What is the formula to work this out?
    Is this a trick question? There are 2 answers.

  3. #3
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    I have the solution for your problem but I need your E-mail address or do you want my PayPal E-mail!!

    540

  4. #4
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    lol :D

  5. #5
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    Quote Originally Posted by em99010pepe
    I have the solution for your problem but I need your E-mail address or do you want my PayPal E-mail!!

    540
    I made an autocad draw with the explanations and necessary equations.
    The angle sum of a pentagon is 540º.

  6. #6
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    2 answers Chaz?

    This is what I thought:

    Theory 1.

    The angle sum of a triangle is 180°
    the angle sum of a square is 360°
    therefore the angle sum of a pentagon must be 540°


    Theory 2.

    If triangle is 180° and it has 3 angles ie 60° per angle
    and a square is 360° with 4 angles, ie 90° per angle

    then a pentagon (5 angles) must have an angle sum of 5 x 120° = 600°

    Theory 3.
    Lets just say that a triangle is a really bad circle. So bad it only has an angle sum of 180°.
    Next is a square, a liitle better in the search for a circle. It has an angle sum of 360°.
    Now we know that a circle is perfect and it has 360° in it so its angle sum is 360°. It is a polygon with an infinite number of sides.
    By interpolation, the angle sum of a pentagon is 360°

    . . .

    Any one else got the answer?

  7. #7
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    I found this site on Sum of angles in a polygon.

    http://regentsprep.org/Regents/math/poly/LPoly1.htm

  8. #8
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    Thanks gamer007.

    The answer is 540°

    The formula is 180(n-2) where n = the number of sides of the polygon.

    See also here:

    http://mathworld.wolfram.com/Polygon.html

  9. #9
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    That was me. Looks like I don't have cookies set on this computer or something is a bit wacky here.
    Vaughan

  10. #10
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    Answer 1: the sum of the INTERIOR angles is 540 degrees
    where x= the number of sides using the formula (x-2)180

    Answer 2: the sum of the EXTERIOR angles of any polygon is 360 degrees.

    You did not specify which angles, therefore its possible to have 2 correct answers. ;)

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