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Some of you may have seen this optical illusion before. It appears to be a triangle made up of four parts, that when rearranged create an extra hole that shouldn’t be there. I’ve seen all sorts of ridiculous explanations (see the comments) on different websites, but it is in fact VERY simple. Look at the two triangles within the larger one. The smaller of the two triangles, the blue one, has a slope of .4, or 2/5. Now look at the red one. It has a slope of 3/8, which is .375, not the same slope as the other triangle. This means that off the bat, THIS IS NOT A TRIANGLE. It’s a quadrilateral. You can tell if you look closely that they are not in fact straight. This sort of makes the rest of the illusion moot, because it’s trying to convince you that it’s a triangle. They don’t specifically say that it is a triangle, but they call it figure ABC, when it really is figure ABCD. Since there are four points, and not three, it is possible to make a hole in the “triangle” by rearranging the parts to make it concave or convex. End of story.
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Comments
by Daniel on Aug 27, 2009
Before reading the comment above, I took a look at the illusion and what I noticed was the relationship between the green polygon and the yellow polygon. It seemed to me that by arranging them as they are in the second diagram, there is a space created due to the bottom half of the yellow polygon being two units in width.
by rockouloud2001 on Nov 05, 2009
I don't get it. At all.
by Colum on Apr 02, 2010
Thank you so much!! I should have seen this coming long ago when I saw this on a cereal box. But I didn't. I even cut out the pieces and played with it for a while XD