Let’s take a closer look at that grid.

Maybe you’ve played with this for a while without coming up with a valid domino tiling. It’s definitely not as easy as it looks!

To see why, let’s color this grid like a checkerboard:

(Give this problem another try before reading more. I’ll wait.)

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Okay. The key to finishing here is to notice that every time we place a domino on this checkerboard, we cover up one white square and one green square. No more, no less. But the two missing squares are *both green*. So we’re trying to cover up 32 white squares and 30 green squares with dominoes that each cover one white square and one green square. This is impossible, so there are 0 ways to tile this grid.