Skip to content / Đến nội dung
ThichHocToan.com

2024 AMC 12A Question 18

AMC12 · 2024 AMC 12A

Question 18

On top of a rectangular card with sides of length $1$ and $2+\sqrt3,$ an identical card is placed so that two of their diagonals line up, as shown ($AC,$ in this case).

Question illustration

Continue the process, adding a third card to the second, and so on, lining up successive diagonals after rotating clockwise. In total, how many cards must be used until a vertex of a new card lands exactly on the vertex labeled $B$ in the figure?
  1. $6$
  2. $8$
  3. $10$
  4. $12$
  5. No new vertex will land on $B.$