The 8 \times 18 rectangle A B C D is cut into two congruent hexagons, as shown, in such a way that the two hexagons can be repositioned without overlap to form a square. What is y ?

**Answer Choices**

A. 6

B. 7

C. 8

D. 9

E. 10

The 8 \times 18 rectangle A B C D is cut into two congruent hexagons, as shown, in such a way that the two hexagons can be repositioned without overlap to form a square. What is y ?

**Answer Choices**

A. 6

B. 7

C. 8

D. 9

E. 10