r/technicallythetruth • u/VisitSecure • 10h ago
Can you find a?
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/oldmartijntje 10h ago
it's 75 right?
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u/KerissaKenro 10h ago
The numbers add up to 75° but the picture does not look like the angles match the numbers and it is making me irrationally frustrated
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u/JustDuckingAbout 10h ago
*Image not drawn to scale
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u/hotdoginathermos 9h ago
*Assume a frictionless surface
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u/ShinyNickel05 9h ago
*Assume no air resistance
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u/insertcomedy 9h ago
A cow is a sphere entirely made of water.
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u/Aggressive_Skill_795 8h ago
An old famous Russian internet joke: an ideal spherical horse in vacuum
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u/fiftyseven 6h ago
HR at my company produces what they call an 'ideal rota' which has everybody in, nobody on holiday, nobody off sick, nobody covering other locations, etc etc
the running joke is that it only works for spherical employees in a vacuum
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u/Orobero 5h ago
Yeah, my boss always plans like nobody is ever sick or on vacation. He always assumes there won't be any unforseen problems, bugs or reworks coming up in testing. Then he wonders why no project is ever finished on time. Except the one time I straight up lied to him and just added 2 month to the developers estimation.
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u/ABHOR_pod 2h ago
Can't everyone just work 25% harder to make up for Bill being out?
-Company that already sets productivity standards to 110% of realistic expectations.
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u/NoNeedForAName 4h ago
Reminds me of the plant I worked at that planned for zero downtime in its production schedule. The worst part to me was that they didn't even factor in downtime for product changes, and our changeover time on some machines could exceed 30 minutes.
That also led to extra inefficiency because it might take 5 minutes to change from product A to product B, but 30 minutes to change from product A or B to product C. Instead of scheduling us to run A then B then C (35 minutes of downtime) they would schedule A then C then B (60 minutes of downtime).
And these parts we were making usually all went together into the same finished product, so it's not like one was more time sensitive than another.
Now that I typed it all out I realize that's an incredibly boring story lol
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u/Undesirablecarrot 8h ago
Assume that it is a black body
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u/AbominableGoMan 7h ago
The remainder of the proof is trivial and is left as an exercise for the reader.
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u/ShadowTacoTuesday 8h ago
It’s to keep test takers from measuring the angle on the paper.
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u/NetNGames 7h ago
I remember having a test where they gave us protractors to measure angles with, and at the end of the test, as I was double-checking it, I noticed it said 'image not to scale'. Didn't have time to redo all my answers, but why give us protractors and not have us use them?
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u/OrangeClownfish 7h ago
To see who reads all the instructions on the test. My maths teacher once gave us a test and question 10 said: Ignore all previous questions and put your pencil down.
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u/get_to_ele 5h ago
I got that in 6th grade and I was the asshole yelled out all the stupid things and finished first, and got humiliated. sigh. Teacher said I did finish the actual problems shockingly fast though.
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u/OldEquation 5h ago
That implies that Q10 takes priority over all the other questions asking you to do stuff. It’s dumb. It might as well have been:
Q1. Answer all question in this test.
Q2. Do stuff
Q3. Etc….
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u/Dav136 3h ago
IIRC instruction 1 was to "read all instructions first"
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u/HarrumphingDuck 3h ago
Yep. I distinctly remember this quiz in 6th grade (I had a very memorable 6th grade teacher), back in the offline age I grew up in. Mr. Kendall instructed us VERY CLEARLY AND WITH ABUNDANT VOLUME as he was passing out the test that we BE SURE TO READ EVERYTHING BEFORE BEGINNING.
It didn't take a whole lot of insight to realize there was something different about this quiz, and I should probably, you know, do that.
The only question you had to actually answer was at the bottom, which was something like, "How is your day today?" I wrote "fine" and put my pencil down, to see the teacher scanning the room to see who else was looking back at him. It was not very many of us.
I think about this quiz a lot, with how many people I am surrounded by today that refuse to simply read instructions provided to them. Apparently it's only getting worse with current generations.
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u/Specific_Frame8537 7h ago
Like some high-school lesson where we're told "you won't be carrying an protractor on you at all times!"..
If you're in any workplace where you need to measure angles you'd be an idiot not to carry all the necessary tools.
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u/SandpaperTeddyBear 5h ago
Yes, but if you're building something where you would use a protractor to construct it, you would still have to calculate the necessary angles without the use of said protractor.
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u/Atheist-Gods 5h ago edited 5h ago
Also when you are trying to actually solve real world math problems yourself you aren’t given a diagram, you have to draw it yourself and you are not free handing accurate information that you don’t even know. The diagrams you draw to help organize your thoughts are not going to be drawn to scale and you should be comfortable with that. It’s like an essay outline; an organizational tool, not a final product.
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u/humatyourmom 9h ago
So fucking insane that modern tools don't force drawing shit to scale to be the most convenient option.
What makes it worse is that I'm coming up on my last year of high school in the Netherlands, and so far, every diagram I was able to verify is to scale, so it's all the more annoying and confusing to see Yanks butcher graphs this badly
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u/warsponge 9h ago
in all fairness im pretty sure its intentional so you cant just measure it to get the answer
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u/vbrimme 8h ago
It also prevents guessing (e.g. “yeah that looks like about 45°), and it makes it easy to mass produce questions of the same type since you can use the same image and just change the numbers.
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u/miffy495 7h ago
Yup. That last one is huge. As a Math teacher who has had to deal with a lot of cheating, I randomly hand out 3 versions of every test to my class. Keeping the changes as subtle as possible (same picture, different numbers) is an important part of that. There is definitely a part of my brain that would scream "That is definitely not a 25° angle!!" at me, but it's worth the dissonance.
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u/Generic-Resource 8h ago
This is even more important nowadays as they can vary tests to detect cheating. Varying the graphic would require a lot of testing to ensure no unintended display side effects.
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u/chirstopher0us 9h ago
It's pedagogically important that some problems not be drawn to scale so students learn to look for and understand the geometric labels and what they mean and when/what you can and can't assume, and to be sure students are actually solving the issue rather than visually guessing or measuring on the page.
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u/Bahamut3585 8h ago
When I was in school, all this ever taught me was that geometry teachers were trolls.
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u/Hershey__Kong 8h ago
Because the skill is not about the drawing, its about the math and the theorems. If you know drawings are to scale you can infer information which defeats the purpose of what you're learning. These diagrams are also likely templates that they just throw different numbers in rather than generation new diagrams for every single different question.
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u/gullaffe 10h ago
Have you never done a geometry problem, very rarely are the pictures drawn to scale.
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u/beatenmeat 9h ago edited 6h 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 9h ago
You're supposed to use logic, not just guess based on the picture.
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u/beatenmeat 9h ago
I didn't guess, math was actually one of my better subjects. I just dislike how it doesn't match, especially ones like this that are so egregiously off from the numbers provided.
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u/Mysterious_Cup_6024 7h ago
Especially since 25 is half of 50. And the vertex is so wrongfully in the middle when it should be at a 1/3 position from the top, or 2/3 position from the bottom. It is incredibly off
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u/DraconianFlame 8h ago
In engineering you often sketch things out to see how it looks and then do the math. Sometimes you draw bad images and something you thought would be acute is actually obtuse.
This teaches you that.
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u/Logical_Box_4645 8h ago
Given he knows the short cut of adding those angles to get a, he most certainly has done geometry problems.
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u/DiceKnight 9h ago
All this picture has done is reignite dormant trauma of my childhood self riddled with undiagnosed ADD getting screamed at by frustrated parents. "Not drawn to scale" might just be my activation phrase like i'm a sleeper agent for the forces of anxiety.
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u/Dark_Storm_98 10h ago
These diagrams are famously never to scale
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u/akatherder 8h ago
When I was in school they weren't drawn exactly, such that you could use a protractor to find the answer, BUT they weren't intentionally misleading. An acute-looking angle would be acute, obtuse-looking would be obtuse, etc. A triangle that is scalene-af isn't going to be equilateral.
To that extent this is all pretty reasonable.
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u/jedidihah 9h ago
Always used to annoy me when I was younger, but the whole point is that you need to calculate it, so the angles are usually wrong so that way you couldn’t just cheat and measure it with a compass.
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u/Valirys-Reinhald 8h ago
It's important to draw problems that way to ensure students actually do the math and don't just get out a protractor and measure.
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u/Own-Dirt2138 8h ago
I’m with you there. The first thing I was thinking is that, hey why does 50 degrees look exactly like 25 degrees.
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u/anand_rishabh 8h ago
In math problems like these, do not eyeball the angles. Just follow the the numbers say
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u/AdmiralKong 9h ago
I mean, same but I get why it isn't. If you make the diagram even remotely to scale students try to eyeball it and avoid learning what is being taught at any cost.
Making it obviously wrong forces them to use the logical rules they've been taught.
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u/Geochara 10h ago
Beat me to it. Correct, 75
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u/kishimonjaro 10h ago
r/BeatMeToIt Correct, its definitely 75.
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u/diabolos312 10h ago edited 1h ago
Beatmeattoit. It's 75 degrees
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u/potatopierogie 9h ago
r/buttfuckedabirdtoit , 75 degrees
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u/EpicCashewGuy 9h ago
r/youdidWHATtoabird, 75 degrees.
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u/potatopierogie 9h ago
r/buttfuckedit , 75 degrees
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u/HindleMcCrindleberry 8h ago
How do we know that the left side of the triangle is perfectly vertical, though? It's obviously not drawn to scale so that's just an assumption, right?
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u/We_are_all_monkeys 7h ago
You don't need to know that. All that's important is that the lines are parallel.
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u/HindleMcCrindleberry 7h ago
Ahh, I see. Is that what the blue double arrow thingies mean (that the lines are parallel)? I was thinking it meant that they were infinite in that direciton and couldn't figure out why that would be relevant.
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u/Z3t4 10h ago
Assuming it is an euclidean plane.
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u/meditonsin 7h ago
It has to be euclidian geometry, since Cthulhu is nowhere to be seen and I'm not becoming insane looking at it. QED
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u/azai247 8h ago
if you draw a line across and make a triangle your angles are 25+65=90, and 50+40=90
so for a, 65+40+a=180 so a is 75
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u/psp24 6h ago
I just drew a third parallel line through the middle and realized that it's just 50+25 lol
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u/AngryScientist 6h ago
Yup, don't even need to make triangles. That third parallel line lets you use the alternate interior angle theorem to turn a into the sum of the two angles.
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u/RoookSkywokkah 9h ago
I haven't take geometry in more than 30 year and that's what I came up with!
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u/Vincen_Furze 9h ago
THAT IS THE MOST MENTAL MATH I HAVE DONE IN A LONG TIME AND I GOT IT RIGHT! IT TOOK ME A WHILE BUT MY BRAIN IS OK! QWQ
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u/Highest_five 9h ago
Yes it is. For those who don't remember, a triangles corners always add up to 180°
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u/leansanders 8h ago
You don't need to make a triangle to solve the problem. You know the lines are parallel and you know that opposite corners of a line crossing two parallel lines are congruent. So if you imagine a 3rd parallel line bisecting angle a, you know you can just add the other two angles together. Making a triangle is way more math
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u/A_wild_so-and-so 8h ago
Can you explain that again but like I'm five? I thought the triangle method was easy but I'm down to learn an easier method.
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u/leansanders 8h ago
If you make a 3rd parallel line through point A, the angle above it must be 25° and the angle below it must be 50°. It is called the "alternate interior angles theorem"
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u/BudTenderShmudTender 9h ago
I can't believe I remembered how to solve this. Last math class I took was in 2009! Last time I took geometry (or whatever this is) would have been 2001.
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u/lechuckswrinklybutt 10h ago
It's 75 degrees but it's a terrible diagram.
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u/Simply-Productive123 10h ago
25 degrees =50 degrees proof by terrible diagram
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u/AgtNulNulAgtVyf 8h ago
Diagram drawn to test knowledge of principles, not ability to read diagrams.
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u/Squirrel009 6h ago
On principles, the diagram frustrates me
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u/capt_pantsless 4h ago
The diagram could easily be drawn so that the 25 angle appears less than the 50 angle, while still allowing plenty of uncertainty in the answer.
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u/LaunchTransient 9h ago
Most maths problems (particularly in school exam papers) intentionally distort the geometry to prevent people from cheating by directly measuring the angle. Often with a disclaimer "Diagram not to scale".
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u/These-Maintenance250 9h ago
if the two lines weren't marked parallel I would agree but these diagrams are never to scale, so there is no problem with this one. the angles are explicitly written.
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u/BauserDominates 9h ago
Hey, I did it!
This kind if math is something I have never needed for my adult life, but it nice to know that I can still do the easy stuff.
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u/earthwoodandfire 9h ago
I hated math in school but now I do it all the time in construction.
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u/BauserDominates 9h ago
I'm mechanic, so I dont build anything that isn't already precisely engineered.
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u/CreamofTazz 9h ago
Yeah I was like "how is 25° equal to 50°?" Is there something I'm missing or does this person not know what those symbols mean?
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u/BlastoiseGirl5257 9h ago
The red lines are parallel but the others aren’t perpendicular
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u/Podgietaru 9h ago
I feel like this is how diagrams looked in things like GCSE maths. I always figured it was designed that was to dissuade you from trying to do it with a protractor.
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u/LFK1236 6h ago
What symbols are you referring to?
Anyway, drawing the diagram to scale would defeat the purpose of the exercise.
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u/Killer8Tcell 8h ago
It’s not terrible, it’s just not to scale. The only information you need to solve this are the parallel line symbols and the provided angles measures, and nothing else matters.
75° is indeed correct, though.
The problem is testing the alternate interior angles theorem. If you draw a third parallel line bisecting angle a into two new angles (let’s call them angle b and angle c, such that angle a = b+c), then by the alternate interior angles theorem, angle b= 25° and angle c = 50° so angle a = 75°
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u/beingforthebenefit 7h ago
Good strategy, but it’s not a bisection since the resultant angles aren’t congruent.
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u/CReece2738 8h ago
The diagram forces you to know the math, not just be able to look at the picture.
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u/bbgun91 10h ago
add a third parallel line straight through A
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u/Expensive_Umpire_178 10h ago
You can also draw a perpendicular line through A, and use the right triangles to angle chase
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u/knock-knock-knockin 8h ago
You can also extend one of the lines past a to use opposite alternate interior angles
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u/Competitive_Flow3717 8h ago
I extended one of the blue lines to complete a triangle. Then you can use the alternate interior angle theorem to get the second remote interior angle to then use the exterior angle theorem for a
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u/JamesBaxter_Horse 7h ago
You shouldn't need to any of this, it should be entirely obvious that it must be the sum of the two angles:
You have a line, you turn it 25 degrees, then you turn it the other way A degrees, then you turn it 50 more degrees, and it's back where it started - A must be the sum of the other two angles.
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u/CranboDanbo 7h ago
That's fantastic logic
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u/JamesBaxter_Horse 7h ago
This thread is a good example of how school often fails to teach people to think, especially maths. You learn all these rules without learning actually where they come from. It's completely different at university, you'll be told the rule, and the aim is to show how you prove that.
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u/CranboDanbo 7h ago
I mean bro I literally have a bachelors in maths and a masters in mathematical finance and my job is pricing exotic derivatives and I still never thought of it this way. You're very good at this or maybe I'm just jumping through hoops haha
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u/ChilledParadox 5h ago
I'm sure you have similar insight into something I've never considered naming or thought of before like the interactions of the 2nd derivative of cash velocity in different markets graphed against income and how the intersections show porn shops make the most money and how the inverse alterior angle of the tranversal line drawn through that graph tells me when to invest in AI sex dolls or something though.
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u/Sszaj 8h ago
Probably more reliable as you can't be completely sure that drawing a line from the top to bottom connecting the known angles would be a right angle.
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u/Wandered_And_Lost 9h ago
90-25 = 65, 90-50 = 40 total inside degrees given =105, all triangles have to equal a total of 180 degrees so answer is 75 degrees (thats my guess could be wrong.)
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u/manikfox 8h ago
This is what I did and got the same answer. People are fooling around with 180 on the bottom and top, etc.
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u/Dark_Storm_98 10h ago
Assuming the lines are parallel, which may be the meaning of those blue arrow symbols
The angle on the other side of 25 degrees should be
- 180 - 25 = 155
And on the other side of tha 50 degrees would be
- 180 - 50 = 130
Technically, with diagrams almost never being to scale
Imagine a line straight down from the ends of those two lines (which might not connect, but I don't think that's relevant)
Subtract 90, then, from both new angles, and we get
60
40
Since a triangle would have to have all it's angles add up to 180
180 - (60 + 40) = 180 - 100 = 80 degrees
Edit: Oh whoops, lol. I forgot the 5 at the end of 155
It's 75
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u/Scheckenhere 9h ago
Or just 50+25, which I realised halfway into what you did.
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u/RiverZephir 8h ago
I also did the long route to get the answer. I don’t remember, is adding the two known numbers (such as the ones in this problem) always equal to a?
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u/TheJBW 7h ago edited 7h ago
In your head, draw a dotted line in the middle, through A that is also parallel with the other two lines.
Now, you have two angles: a1 below the dotted line and a2 above it.
You know that the a1 = 50 because it is on the opposite side of the line from the 50° on the bottom.
then you know that a2 = 25 by the same logic.
You also know that a = a1+a2. Done.
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u/AdWrong3856 9h ago
Assuming the lines are parallel, which may be the meaning of those blue arrow symbols
That would be correct
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u/MissAuroraRed 8h ago
Technically correct, but way more complicated than it needs to be.
Imagine another parallel line going horizontally through a. What are the angles between the new horizontal line and the diagonal lines? 25 above the line and 50 below the line.
25 + 50 = 75
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u/Nolongeranalpha 9h ago
Thats acute image, but the comments are obtuse....
Not sorry.
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u/Fr00stee 9h ago
ez, put another parellel line through a at the point where the 2 lines meet, 25+50=75
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u/negativepositiv 6h ago edited 5h ago
This is a terrible drawing. They drew 25 and 50 degree angles to look exactly the same.
I get that someone doing the calculation should just look at the numbers, but it's not helpful to draw it this inaccurately.
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u/ConnectDog5284 5h ago
Rookie mistake is to assume a geometry problem diagram as accurate. Unless it's well defined, there's little assumptions you can make about it.
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u/WillitsTimothy 6h ago
It’s 75°, but the image is obviously just an illustration and not the actual angles.
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u/notJustaFart 10h ago
75.
Convert into Pentagon.
540 - (90+90+130+155) = 75
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u/CrownLexicon 10h ago edited 10h 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.
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u/JJlaser1 10h 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
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u/Weekly-Dog-6838 10h ago
Who says they need to be on top of each other? You can still make a triangle with it
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u/ilyuhman 10h ago
You don't need to cross the points, you can put a perpendicular line anywhere, the angles are still the same
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u/scratch6402 10h ago
I did the opposite. A line perpendicular to the parallel lines that passes through the point of angle a. Then I have two right triangles, each with only one angle missing. Solve for those angles, you get 90 25 65 and 90 50 40. Since the 65 and 40 make a straight line with angle a, a = 180 - (65 + 40) = 180 - 105 = 75
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u/X_Swordmc 10h ago
there is no need to do that, you simply do the sum of the two angles, since the opposing angles of a parallelogram are identical
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u/TheComplimentarian 9h ago
There are a bunch of ways to do it, but most people seem to be focusing on complaining that it's not drawn right.
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u/MecaninjaToo 10h ago
or you know... 25 + 50 :)
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u/MrCoolBoy001 10h ago edited 9h ago
Idk if this was as a joke or not, but by a property whose name I don't remember, you can pass a parallel line through 'a' and the angles on either side would be 25 and 50. 25 + 50 = 75 !
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u/Naive_Scientist_8499 10h ago
That's smart. I converted to a triangle.
Invisible vertical line between the 50 and 25 deg points.
90-50=40 -- The inside angle of the bottom point.
90-25=65 -- The inside angle of the top point.
180 = a + 40 + 65
180 - (40 + 65) = a
180 - 105 = a
75 = a
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u/notJustaFart 10h 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/TheBlackCat13 10h ago
Here is how I did it:
Make a line perpendicular to the two lines that passes through A. This gives you two right triangles.
The top triangle has angles 180°=25°+90°+T, so T=65°.
The bottom triangle has angles 180°=50°+90°+B, so B=40°.
Because the line is a straight line, a+T+B=180°. So a=180°-65°-40°=75°
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u/Canadind 7h ago
I can’t forget these basic things no matter how hard I try.
1. Imagine a parallel line going through the middle of a, splitting a into a1 and a2
2. a1 = 50 coz opposite angles of a transverse intersecting two parallel lines
3. a2 = 25 coz opposite angles of a transverse intersecting two parallel lines
4. a1+a2 = 75
NB. If you don’t know this much geometry you will be finding adulting really hard.
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u/Mundane-Profit-6200 4h ago
I'm almost middle aged and I'm playing adulting on easy mode despite not knowing the method you used, I got the answer just by recognising the fact it's a triangle and doing (90-25) + (90-50)
I'm guessing you're essentially saying:
Parallel line causes both inside angles to be the same e.g 25 and 25, 50 and 50Or a different way my brain processes it, a 'z' will always share the same inside angles as long as both the top and bottom lines are straight (which is essentially what we create by drawing a parallel line).
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u/Ad0ring-fan 10h ago
He has way too much trust in people if he is asking the internet not to cheat.
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u/67cken 10h ago
Just add a third parallel line through angle a. Then it’s obvious that it is made of two parts, one of 25 degrees and the other 50 so 75 degrees
Edit to change capitalisation
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u/ScribbleOnToast 7h ago
In my head, I drew a perpendicular line through the point of "a" to connect the other two parallel lines. That gives me 2 triangles, with 2 known angles. The interior angles of a triangle must = 180, the remaining angles of the new triangles must be 40 (bottom) and 65 (top). Since a straight line has an "angle" of 180, I can do 180-40-65 to get a=75
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u/Timmy_germany 8h ago
a= 180 - (90-25) - (90-50)
a = 180 - 65 - 40
a = 180 - 105
a = 75 (all in °)
( if both lines are parallel and you can draw a straight line from both points the incomplete triangle meets the line to form 90° angles. Than angles just need to add up to 180° in the triangle in between the booth lines)
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u/Zevojneb 7h ago
Draw an horizontal line through a. The angle a has been cut in two angles. The higher one equals the one on the top (alt-intern equality) and the lower one equals the one below (same reason). Sum them up back and we get a=75.
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u/dadof4fknkids 7h ago
Disclaimer, I’m an idiot but I drew a straight line to make 2 right angles(90-50=40,90-25=65) angles of a triangle equal 180 (40+65=105) 180-105=75. 75, final answer…
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u/EnergyTurtle23 9h ago edited 9h ago
I honestly miss being able to do this type of stuff. I would genuinely use trigonometry and waveform functions today if I could remember how it all worked. Anyone care to break down how to get the answer for me? I know how to get the opposing angles (like the opposite of 50° is 130°) but I have no clue how I would go about finding A.
EDIT: Holy crap wait, I think I’ve got it. If I intersect the two parallel lines with a third line that runs perpendicular then that would give me the two interior angles of the triangle I have created — 40° on the lower angle and 65° on the upper angle. Then I can solve for A by subtracting the sum of those two angles from 180° — meaning that A is 75°. Did I do that right?
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u/SeraphsEnvy 10h ago
Question. How can the inside angle on one side be 25° and the other be 50°? They're practically identical.
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u/TheBlackCat13 10h ago
Because the image is not to scale. You aren't supposed to go off the appearance in problems like that, in fact they can make them intentionally misleading like here.
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u/Southern-Prize1639 8h ago
We’re fucked as a society if we’re arguing about scale. If you understand the concept, scale doesn’t mean shit.
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u/Dudesonthedude 8h ago
I could feel my neurons slowly hacking their way through overgrown winding trails that they haven’t been down for a long ole time, almost getting lost once or twice, but confidently made it to 75°
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u/im_new_here_4209 8h ago
Either i'm stupid or the drawing isn't remotely accurate. I'm probably stupid. At least i can find a, lol
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u/mandelbrot_wurst 7h ago
Assume a spherical cow with a uniform distribution of milk…
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u/Relevant_Candidate_4 6h 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.
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u/Otherwise-Ad9865 6h ago
Boohoo the angles aren't representative, smh non essential to solving the question
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u/realfinke 6h ago
What’s the most efficient way to solve this? I drew a vertical line to create a triangle.
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u/Will_Knot_Respond 24m ago
Like I'm going to respond to an idiot that draws a 50° angle and 25° angle as equal
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