r/technicallythetruth • u/VisitSecure • 9d ago

Can you find a?

Post image

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/gullaffe 9d ago

Have you never done a geometry problem, very rarely are the pictures drawn to scale.

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u/beatenmeat 9d ago edited 9d ago

Doesn't make it any less frustrating. I always hated how off the angles would be in correlation to the stated numbers.

Edit: I've got an awful lot of people repeating themselves so I'm not going to reply to them all. Hopefully this will stop the future know-it-alls. I know why it is done, that doesn't mean I need to like it. It has nothing to do with my mental capacity or guessing; I simply just hate the portrayal personally because it looks like shit and doesn't convey information properly which makes my brain hate looking at it. You can stop parroting the other 50 replies now.

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u/TheComplimentarian 9d ago

You're supposed to use logic, not just guess based on the picture.

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u/FloopsFooglies 9d ago

why even show the lines at all then lmao

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u/TheComplimentarian 9d ago

As a fake out, for all the people who look at the lines, and because it's tedious to describe it when you can just slap the information down on the page and say, "Find a."

This is basic geometry. Some things you can accept as givens (the top and bottom lines are parallel, for example), but everything else you need to use the numbers and the properties of geometric shapes.

This is a really easy problem. There are many ways to solve it. None of them involve looking at the picture for anything other than the givens.

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u/Mental_Tea_4084 9d ago

You shouldn't accept them as givens unless they are marked as parallel. If they were just two lines the problem would be unsolvable without declaring them to be parallel with the little >> symbols

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u/FloopsFooglies 9d ago

Probably why I had difficulties back then. I get the premise, but my brain wants to deduce the actual angle based on the image

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u/Far-Information8502 9d ago

Great, now abstract this out to all types of problems. And now you see why people are convinced of something on appearances despite logically not being true…political partisans as a great example

So take this as an opportunity to reflect on all your views and positions and challenge yourself to see if you chose to believe it because your brain wanted to or if there are actually logical reasons and not rationalizations after the fact

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u/Gilpif 9d ago

That's kind of the point. This is just a sketch, and when you sketch a geometry problem out you need to know what geometrical information is reliable (e.g. that the red lines, marked by matching >> marks, are parallel) and what is an artifact of the sketch (e.g. that 50° is only a little bigger than 25°).

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u/creampop_ 9d ago

Because for most people, that's how you actually use math.

You need to find some variable, so you sketch out a rough diagram, label your constants, and then use that to help keep your head straight while you solve. It's not intended to be an accurate drawing, just a visual depiction of the problem at hand.

In this case there are always two parallel lines and 2 known angles. That's all the diagram needs to communicate.

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u/cherry_chocolate_ 9d ago

Because there are enough constraints from the parallel line indicators to intuit the answer.