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2021 AMC 12C Question 21

AMC12 · 2021 AMC 12C

Question 21

Let $ABCD$ be an isosceles trapezoid with $\overline{BC} \parallel \overline{AD}$ and $AB = CD.$ Points $X$ and $Y$ lie on diagonal $\overline{AC}$ with $X$ between $A$ and $Y,$ as shown in the figure. Suppose $\angle AXD = \angle BYC = 90^\circ,$ $AX = 3,$ $XY = 1,$ and $YC = 2.$ What is the area of $ABCD?$

Question illustration
  1. $15$
  2. $5\sqrt{11}$
  3. $3\sqrt{35}$
  4. $18$
  5. $7\sqrt{7}$