http://205.252.89.156/triangle/Triangle.gif

I posted this on the General Questions board as well, but everyone who’s anyone knows that the people with the biggest brain-boxes hang out on MPSIMS.

This has been driving me crazy. Someone please explain to me, in the simplest terms possible, how the hell does this work?

Look *very* carefully at the angled line, and compare the hash marks it hits in the bottom example to the hash marks hit in the upper example. On the bottom example, you’ll find that the angled line hits the hash marks at a *slightly* higher point each time. Not enough of a difference to be immediately noticeable, but if you look carefully, you’ll see it. But that small difference, multiplied over each box, makes enough space to cover the “empty” box.

As a better mathematical explanation- the angles in the red triangle are different from the angles in the green triangle (the green triangle has a side ratio of 2:5, the red of 3:8; if they were the same angle, the red triangle would be a ratio of 3:7.5). So what you think is a “straight line” on the whole sum is actually two slightly angled lines; in the top example, they bend concave (into the whole sum), and in the bottom example, they bend convex (out of the whole sum)- in order to keep the area the same (because you’re dealing with the same parts), that extra space (the difference between the convex part and the concave part) has to come from *somewhere*, and thus you have a missing box.

Again, look at where the angled line crosses the hashmarks, and you’ll notice the slight difference between the two.

It’s an optical illusion … sort of. It’s been posted here before.

**Moderator’s Notes:** And for the record, please **do not** cross-post your topics again. This is considered bad form 'net-wide. I’m gonna lock this thread since it’s currently duplicated elsewhere.