UKMT Pink Kangaroo, 2025

Geometry Difficulty 2.0 Junior Find the answer United Kingdom

A circle with centre $O$ and radius $10\text{ cm}$ is given. A square $OPQR$ is drawn inside the circle, where $Q$ is a point on the circle. What is the area of the shaded triangle $PQR$ ?

(A) $25\text{ cm}^2$ (B) $30\text{ cm}^2$ (C) $35\text{ cm}^2$ (D) $40\text{ cm}^2$ (E) $50\text{ cm}^2$

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