# Which Line is Longer?

The Optical Spy box is split into the top third and the bottom two thirds. So which line is longer, the diagonal splitting the top third A-B or the diagonal splitting the bottom two thirds B-C?

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### 4 Responses to Which Line is Longer?

1. Phil Krause says:

They both look the same length to me, but there must be something wrong with that shadow.

2. Steve B says:

So, if we were to assume that the box faces are rectangles where the shorter side is 1 unit, and the longer 3, then:

AB = âˆš2 = 1.414213562

BC = âˆš5 = 2.23606798

Which makes BC the longer as you would expect. But I guess that it would be dangerous to assume (or expect) that all is as I think it appears, and maybe the answer is AB = BC

• Deskarati says:

I think this is the best answer that could be given. Well done Steve.

3. Phil Krause says:

But those are the true lengths. We are viewing from an angle with perspectives. The shadow still doesn’t work for me.