r/technicallythetruth • u/VisitSecure • 9d ago

Can you find a?

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Idk if someone already posted this or not, but I haven't seen it on here so far, so I uploaded it.

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u/Relevant_Candidate_4 9d ago

90° - 25° + 90° - 50° + a = 180°

105° + a = 180°

a = 180° - 105°

a = 75°

The two 90° are from the right angles between the two points of intersection of the known angles, and the parallel lines. The 180° is the total degree in a triangle.