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2017 AMC 12A Question 24

AMC12 · 2017 AMC 12A

Question 24

Quadrilateral $ABCD$ is inscribed in circle $O$ and has sides $AB=3,$ $BC=2,$ $CD=6,$ and $DA=8.$ Let $X$ and $Y$ be points on $BD$ such that $\dfrac{DX}{BD}=\dfrac{1}{4}$ and $\dfrac{BY}{BD}=\dfrac{11}{36}.$ Let $E$ be the intersection of line $AX$ and the line through $Y$ parallel to $AD.$ Let $F$ be the intersection of line $CX$ and the line through $E$ parallel to $AC.$ Let $G$ be the point on circle $O$ other than $C$ that lies on line $CX.$ What is $XF\cdot XG?$
  1. $17$
  2. $\dfrac{59-5\sqrt2}{3}$
  3. $\dfrac{91-12\sqrt3}{4}$
  4. $\dfrac{67-10\sqrt2}{3}$
  5. $18$