Help with finding the area of this irregular octagon? Watch

Epel.dh
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#1
Report Thread starter 5 years ago
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Hi!

I'm having trouble with a trig problem and I don't know if it's possible to complete.

I'm trying to work out the area of the overlap. I know all the angles (the shapes overlap one another at 45 degrees) and all the sides of the two shapes.

It would be great to know if it's calculable...and if so, a hint would be greatly appreciated

Thank you!
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ghostwalker
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#2
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(Original post by Epel.dh)
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As it stands, I don't think it can be done. If you slid the diagonally orientated rectangle from bottom right to top left by a small amount, the amount of area in green will change. So, you need more information to fix the two rectangles in position: Can you get that from the original question?
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Epel.dh
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That's a really good point, I hadn't even realised that.

But assuming they cannot be rotated, do you think it's possible to find using trig?

Edit - Also there's nothing else provided :confused: Ghostwalker, I think you're right
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Tortious
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(Original post by ghostwalker)
As it stands, I don't think it can be done. If you slid the diagonally orientated rectangle from bottom right to top left by a small amount, the amount of area in green will change. So, you need more information to fix the two rectangles in position: Can you get that from the original question?
I don't know how I'd do it yet, but is it possible to say that the "big" (offcut) triangle(s) and the "little" triangle(s) are similar, and to use this to find the lengths of their sides?

EDIT: In hindsight this seems to be essentially what someone else has done, but by reference to area.
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