this post was submitted on 08 Oct 2024
1121 points (98.3% liked)
People Twitter
5377 readers
1116 users here now
People tweeting stuff. We allow tweets from anyone.
RULES:
- Mark NSFW content.
- No doxxing people.
- Must be a tweet or similar
- No bullying or international politcs
- Be excellent to each other.
- Provide an archived link to the tweet (or similar) being shown if it's a major figure or a politician.
founded 2 years ago
MODERATORS
you are viewing a single comment's thread
view the rest of the comments
view the rest of the comments
All these people saying its 135 are making big assumptions that I think is incorrect. There’s one triangle (the left one) that has the angles 40, 60, 80. The 80 degrees is calculated based on the other angles. What's very important is the fact that these triangles appear to have a shared 90 degree corner, but that is not the case based on what we just calculated. This means the image is not to scale and we must not make any visual assumptions. So that means we can’t figure out the angles of the right triangle since we only have information of 1 angle (the other can’t be figured out since we can’t assume its actually aligned at the bottom since the graph is now obviously not to scale).
Someone correct me if I'm wrong.
135 is correct. Bottom intersection is 80/100, 180-35-100 = 45 for the top of the second triangle. 180 - 45 = 135
You're making the assumption that the straight line consisting of the bottom edge of both triangles is made of supplementary angles. This is not defined due to the nature of the image not being to scale.
Unless there are lines that are not straight in the image (which would make the calculation of x literally impossible), the third angle of the triangle in the left has to be 80°, making the angle to its right to be 100°, making the angle above it to be 45°, making the angle above it to be 135°. This is basic trigonometry.
Yes.
But that doesn't mean that line must be straight. It just means if it isn't, you can't derive x.
Except for the part where it's a single straight line segment, as depicted in the image. Showing the complimentary angles as an unlabeled approximately right angle is within convention. Showing a pair of line segments that do not form a straight line as a straight line is not.
Exactly.
Add to this that
xis literally impossible to calculate if conventions are not assumed, and absolutely possible to calculate if conventions are followed. Assuming the conventions won't hold is an irrational position.What you say makes no sense.
The problem is LITERALLY unsolvable if we can't assume that all the lines are straight.
The schematic was OF COURSE purposefully drawn in a way to make the viewer assume that the third angle of the left triangle is 90°, making the angle to it's right also be 90°, but the point of the exercise is to get the student to use ALL the given information instead of presuming right angles.
And NO, assuming all the lines are straight is NOT unreasonable, it is the only way that the problem could ever possibly have a solution.
I'd say that the shape on the left has what appears to be a little kink right near X, so one might infer that the shape on the left might be a quadrilateral. There are blatantly obvious vertices that are not labeled as such, so we can't assume that the not-quite-straight line is supposed to be straight since other angles are also not explicitly indicated as vertices...
Reasonable assumptions are a fundamental requirement for communication. It's not that you are wrong in what you are saying. There is a chance that the poser of the question made a visual representation of the triangle's sides appear to be complementary and appear to construct a straight line across their bases while not actually definitively indicating them as such.
The way these triangle's are represented is already skewed so perhaps that is what they are trying to do.
The thing is though, at that point they are defying convention and reasonable assumptions so much that they aren't worth engaging seriously because it's flawed communication.
The version people are choosing to answer seriously is equivalent to a guy holding up a sign that says "ask me about my wiener to get one in a flash for free!" while standing next to a hot dog stand. If you ask he flashes his junk at you and says cheekily "haha you just assumed wrong! Idiot!"
That's already dumb enough but some people could see the clues that suggest he was actually intended to flash people the whole time through a series of reasonable assumptions about his outfit lacking pants or the hit dog stand not even being turned on.
Your argument that we can't assume the line at the bottom is straight is like saying we can't assume the theoretical trenchcoat man won't toss a rabid dachshund he was hiding under the coat at us because the hot dog stand has no buns or condiments on it.
You might not be provably wrong but it's really not worth thinking like an insane person just because a few conventions were defied
So why do you assume the diagram depicts Euclidian space? Why do you assume the numbers are base 10? Why do you assume the question is in English, not just some language that looks like English but has different semantics?
Following your logic, there is no evidence that these are triangles and it is never stated, therefore none of these lines might be straight and the discussion is irrelevant.
There is also no evidence that these are lines at all and not just unconnected points that are offset on a subpixel scale. Or indeed there is no evidence that they are using base 10 numbers or aren't asking a completely different question in an invented language that just happens to look like English but has totally different semantics.
The people claiming it is unsolvable because one 110/80 degree pair of angles looks like a 90/90 one are ridiculous.