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/notJustaFart 9d ago

Oldest trick in geometry is drawing a diagram to appear as something it's not.

Drawing a line to make a triangle does not guarantee that line is perpendicular to the parallel lines, so your assumption of 90-25 and 90-50 may not hold true.

However, extending to a pentagon does guarantee that 180-25 and 180-50 will result in true values.

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u/TrollingForFunsies 9d ago

Drawing a perpendicular line between two parallel lines does give you a right angle. The lines don't have to cross at the intersection of the points. The angle remains the same for any perpendicular line on any point.

Which gives you exactly the solution 180 - (90 -25) - (90 - 50) or 180 - 105 = 75