CEMC Cayley, 2010

Geometry Difficulty 3.0 AMC 10/12 Find the answer Canada

In the diagram, $R$ is the point of intersection of $PT$ and $QS$ , $PQ = PR$ , and $RS = RT$ . If $\angle PQR = 2x^\circ$ , then the measure of $\angle RST$ , in degrees, is

(A) $45 - x$ (B) $90 + \frac{1}{2}x$ (C) $90 - \frac{1}{2}x$ (D) $45 + 2x$ (E) $90 - x$

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