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August 23rd, 2017, 06:42 AM   #1
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Area of irregular Polygon

Hi here is the image of a polygon that I need to find the area of, my dad set me this challenge and I am not back at school yet, for anyone thinking this is homework.

Also, there are right angles at the top right and bottom right
I was thinking splitting it up into smaller triangles but after the first one didn't really know where to go from there.

Last edited by jamesbrown; August 23rd, 2017 at 06:46 AM.
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August 23rd, 2017, 07:22 AM   #2
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Change the lengths (clockwise from top) to: 39,53,37,36,24,12
(easier to work with; change them back later).

Flip diagram sideways so that "53" is on y-axis
and "37" is on x-axis: so diagram fully in 1st quadrant.

Go to town with that: that's all you get from me,
since you did not label your diagram!!

Last edited by greg1313; August 23rd, 2017 at 07:25 AM.
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August 23rd, 2017, 07:46 AM   #3
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Quote:
Originally Posted by Denis View Post
Change the lengths (clockwise from top) to: 39,53,37,36,24,12
(easier to work with; change them back later).

Flip diagram sideways so that "53" is on y-axis
and "37" is on x-axis: so diagram fully in 1st quadrant.

Go to town with that: that's all you get from me,
since you did not label your diagram!!
First off I thought of this method myself and was confused with how you would find the gradient of the lines at the side? And thanks for the advice also I don't understand what you meant by not labelling my diagram - as all I missed out was the 2 right angles which I then added in at the bottom - that was all I was given by my dad so there isn't much else I could have labelled sorrry
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August 23rd, 2017, 07:57 AM   #4
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I meant labelling the vertices;
like AB being the top line (3.86);
then going clockwise, ending up with polygon ABCDEF.
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August 23rd, 2017, 08:05 AM   #5
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Quote:
Originally Posted by Denis View Post
I meant labelling the vertices;
like AB being the top line (3.86);
then going clockwise, ending up with polygon ABCDEF.
oh right my bad

Edit:
still don't understand like if I'm plotting the points, I need 2 values to plot. Like I get the top line cause it's straight but when trying to do BC I wouldn't know where to plot it because I don't know the height nor the length? I only know the hypotenuse if you understand?

Last edited by jamesbrown; August 23rd, 2017 at 08:11 AM.
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August 23rd, 2017, 12:15 PM   #6
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All good my dad added an extra measurement in and was able to calculate it!
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