As shown in the figure, two pieces of paper of equal width are crossed and overlapped. The overlapped part is a quadrilateral. Is ABCD a diamond? Is it a proof, not a reason

As shown in the figure, two pieces of paper of equal width are crossed and overlapped. The overlapped part is a quadrilateral. Is ABCD a diamond? Is it a proof, not a reason

Yes. We can think of these two pieces of paper as two rectangles. Two rectangles are crossed and overlapped to form a quadrilateral ABCD whose opposite sides are parallel and equal. Therefore, ABCD is a diamond