Maths Olympiad Prep

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CEMC Gauss (Grade 8), 1999

Geometry Difficulty 2.0 Junior Find the answer Canada

ABCABC is an isosceles triangle in which ∠A=92°\angle A = 92°. CBCB is extended to a point DD. What is the size of ∠ABD\angle ABD?

(A) 88°88° (B) 44°44° (C) 92°92° (D) 136°136° (E) 158°158°

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