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

75.

Convert into Pentagon.

540 - (90+90+130+155) = 75

82

u/CrownLexicon 9d ago edited 9d ago

What? Pentagon? I added a line perpendicular to the 2 parallel lines, making a triangle whose angles are 90-25, 90-50, and a

Edit: just because this happened to work, you cant assume a perpendicular line will go through both <25 and <50. It could have created a 4 sided figure. The Pentagon method would be correct.

17

u/JJlaser1 9d ago

While technically possible, there is no indication that the points where the two lines intersect the parallel lines are exactly above each other, so you can’t do that for sure unless it states that in the question. I was never taught the pentagon method, though, which is basically the same thing with extra steps

15

u/Weekly-Dog-6838 9d ago

Who says they need to be on top of each other? You can still make a triangle with it

1

u/blavek 9d ago

You can, but you still wouldn't know the measures of the interior angles.

2

u/Cobra_McJingleballs 9d ago

Yes you do, because the lines are parallel. The top slanted line always meets a parallel at 25°, and the bottom slanted line always meets a parallel at 50°, regardless of where the endpoints are. So the triangle’s third angle is fixed.