Comments on: Another Geometry Optical Illusion

By: joe

joe — Sat, 13 Mar 2010 01:26:10 +0000

the trangle in the rectangle has a curved edge

count it every 2 it should hit a corner but on 4th one it is compleatly off

By: ashhole

ashhole — Mon, 08 Mar 2010 02:25:18 +0000

ugh everyones talkin bout angles and junk the solution is even simpler than that. the two orange triangles have the same length when place together to make a square. in the second shape, the two triangles are places farther apart to make a longer length. dummies!

By: Dave

Dave — Mon, 14 Dec 2009 17:41:14 +0000

The angle on the yellow pieces is 20.56 degrees [arctan(3/8)], the angel across the middle of the grey area, not the right-angle corners, is 21.80 degrees [arctan(2/5)].

The 1.25 degree difference actually creates two long thin obtuse triangles that enclose the extra square.

By: random gurl265

random gurl265 — Mon, 09 Nov 2009 17:55:09 +0000

the shapes are the same, just placed to take up more room!

By: Anonymosly

Anonymosly — Fri, 18 Sep 2009 23:24:18 +0000

dude,weird post

By: Paco

Paco — Wed, 12 Aug 2009 14:57:29 +0000

This one’s just stupid. It’s not an illusion at all, just very sloppy drawing.

There’s a thin parallelogram in the core of the right-side shape, which is 0.117 units wide at it’s thickest. The heavy line weights in this picture help to obscure its presence. They’ve also fudged the shape of the yellow triangles on the right to further obscure it.

Essentially, the ‘diagonal’ lines in the left-side shape are not perpendicular to each other. Instead of 90°, they are 88.7546°. This means they are not collinear in the right-side shape, as you would assume. This creates a 1 square unit parallelogram.

By: Ben

Ben — Sat, 11 Jul 2009 04:03:19 +0000

If you actually try to cut up an 8×8 square that way and rearrange the pieces, there’s a really thin hole in the middle of the rectangle which has an area of 1.
I think that explains it.

By: Michael

Michael — Sat, 27 Sep 2008 09:19:00 +0000

Ok. Here’s where I found the problem.
The top of the quadrangle equals exactly 3 squares. At the cross section of the triangle where the top of the quadrangle meets. it should equal 2. (2+3=5). If you look at the 8×8 square, The cross section of the triangle at that point is clearly less than 2 squares. I think that’s a sound explanation.

By: Anonymous

Anonymous — Tue, 11 Mar 2008 04:29:00 +0000

I think there is hole in the middle – very long and very narrow.

By: Paulo Sergio

Paulo Sergio — Fri, 29 Feb 2008 11:44:00 +0000

Hey, Black Mamba, thank you very much. I have a poor English and I was very tired to look for a dictionary. ;)