CEMC Fermat, 2007

Geometry Difficulty 2.0 Junior Find the answer Canada

In the diagram, $PQ = 10$ and $QR = x$ . The value of $x$ is

(A) $10\sqrt{3}$ (B) $20$ (C) $\dfrac{50}{3}$ (D) $\dfrac{20}{\sqrt{3}}$ (E) $10$

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