MathDB
Prove TZ parallel to XY

Source: Argentina TST Iberoamerican 2008 problem 2

August 27, 2009
geometry unsolvedgeometry

Problem Statement

Two circunmferences Γ1 \Gamma_1 Γ2 \Gamma_2 intersect at A A and B B r1 r_1 is the tangent from A A to Γ1 \Gamma_1 and r2 r_2 is the tangent from B B to Γ2 \Gamma_2 r_1 \cap r_2\equal{}C T\equal{} r_1 \cap \Gamma_2 (T≠A T \neq A) We consider a point X X in Γ1 \Gamma_1 which is distinct from A A and B B. XA \cap \Gamma_2 \equal{}Y (Y≠A Y \neq A) YB \cap XC\equal{}Z Prove that TZ∥XY TZ \parallel XY
Back to ProblemsView on AoPS