Art of Problem Solving

2005 AMC 10A Problems/Problem 23: Difference between revisions

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BCDE is a square. Point A is chosen outside of BCDE suck that angle BAC= 120 and AB=AC. Point F is chosen inside BCDE suck that the triangles ABC and FCD are congruent. If AF=20, compute the area of BCDE.  
BCDE is a square. Point A is chosen outside of BCDE suck that angle BAC= 120 and AB=AC. Point F is chosen inside BCDE such that the triangles ABC and FCD are congruent. If AF=20, compute the area of BCDE.  


(A)1/6 (B) 1/4 (C) 1/3 (D) 1/2 (E)2/3
(A)1/6 (B) 1/4 (C) 1/3 (D) 1/2 (E)2/3

Revision as of 12:22, 14 February 2007

BCDE is a square. Point A is chosen outside of BCDE suck that angle BAC= 120 and AB=AC. Point F is chosen inside BCDE such that the triangles ABC and FCD are congruent. If AF=20, compute the area of BCDE.

(A)1/6 (B) 1/4 (C) 1/3 (D) 1/2 (E)2/3