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CEMC Gauss (Grade 8), 1998

Geometry Difficulty 2.0 Junior Find the answer Canada

A regular pentagon has all sides and angles equal. If the shaded pentagon is enclosed by squares and triangles, as shown, what is the size of angle $x$ ?

(A) $75^\circ$ (B) $108^\circ$ (C) $90^\circ$ (D) $60^\circ$ (E) $72^\circ$

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