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UKMT Senior Mathematical Challenge, 2021

Geometry Difficulty 3.0 AMC 10/12 Find the answer United Kingdom

The diagram shows two congruent regular pentagons and a triangle. The angles marked $x^\circ$ are equal. What is the value of $x$ ?

(A) $24$ (B) $30$ (C) $36$ (D) $40$ (E) $45$

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