CEMC Cayley, 1998

Geometry Difficulty 3.0 AMC 10/12 Find the answer Canada

Rectangle $ABCD$ has length 9 and width 5. Diagonal $AC$ is divided into 5 equal parts at $W$ , $X$ , $Y$ , and $Z$ . Determine the area of the shaded region.

(A) $36$ (B) $\dfrac{36}{5}$ (C) $18$ (D) $\dfrac{4\sqrt{106}}{5}$ (E) $\dfrac{2\sqrt{106}}{5}$

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