I can't remember which side is a stone, which is composed of five squares (one in the upper left and one in the middle left, one in the middle right and one in the lower right) cut two times to make a square

I can't remember which side is a stone, which is composed of five squares (one in the upper left and one in the middle left, one in the middle right and one in the lower right) cut two times to make a square

a minor question
The upper right corner of the middle square connects the lower left corner of the middle left and the lower right corner of the lower right