total area of a poylgon?

badgermonkey said:
I don't think so ;)
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I do.

Pick any two vertices with one further vertex between them on the polygon.
Now draw a line between these two vertices.
Consider this line a line of reflection for the vertex in the middle.
Now plot the point on the other side of the line of reflection.
This is your new polygon, it has all sides the same length as before, but a different area.
 
badgermonkey said:
If the sides are the same length it will be the same area iirc :)
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Seriously: "Think of a square and then squish it into a narrow diamond."

The sides are the same length, the internal area most definately is not!
 
badgermonkey said:
If the sides are the same length it will be the same area iirc :)
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Then I don't think you rc :p

As the square gets squished over more and more the area can be calculated by length of base * perpendicular height. (as it is a rectangle with a corner cut off and stuck onto the other side)

Picture a square, 2*2, area = 4.

Squish the vertical sides to 45 degrees, the vertical height will now be 2*sin(45 degrees) = 1.41

area now = 2*1.41 = 2.82

I got sidetracked and guess that I have now been horribly beaten to it :p
 
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BillytheImpaler said:
Why think when you can get computers to think for you?:

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Problem is you've assumed that the polygon contains 2 right angles (which may or may not be the case). As said before, without more information you can't calculate the area.
 
As others have said, since the shape matters ashagplz needs to tell us what the shape is.

EDIT: I know what you're saying, kaiowas. I did that as a proof of concept. :)
 
This should have been the end of the thread:
DaveF said:
If that's all you've got to go on, you can't. Just knowing the lengths of the sides doesn't tell you enough about the shape of the polygon to answer (unless the polygon is a triangle, which it isn't here).
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Arcade Fire said:
No, he was perfectly correct. The area of a parallelogram is the length of its base times its perpendicular height.
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yeah i was off at a tangent (!) was trying to delete it as ytou were typing :)
 
i was trying to calculate the aproximate area that heathrow airport occupies...if you look at a map its basically a polygon bounded by the A4, A30, southern and western perimeter roads.....

map
 
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