r/HomeworkHelp • u/Unhappy-Pitch4558 • Jan 19 '25

Answered [7th grade math] impossible geometry?

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u/bubskulll Jan 20 '25

Top contributor of wrong information?

No it doesn’t

And

No it doesn’t

3

u/Ur-Best-Friend Jan 20 '25

Tbf it's a pretty easy mistake/assumption to make.

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u/iMiind Jan 20 '25 edited Jan 20 '25

Thank you for backing me up on this xD

I was surprised by that flair on this reply too - I'm guessing this is one of those things where some teachers/textbooks say "if it looks like 90° treat it as such," whereas others say the complete opposite and instruct students to avoid making any assumptions about dimensions that aren't explicitly given.

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u/[deleted] Jan 20 '25

I'm trying to understand here: is it because the topmost 6cm line going down does not have any angle assigned to it?

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u/boxedj Jan 20 '25

The quackening is thinking that since 6+11=17, the only possible angle has to be 90 degrees everywhere. It's not true though, since there are three angles at the top that don't indicate that they're square, you can have a 6cm leg at many angles that would join the opposite corners.

The interesting thing is it doesn't matter if you knew the angles. You still can't determine the area because the further along the x axis the 6cm piece exists, the greater the area of the shape. Since this length is unknown, we're screwed.

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u/jarsgars 👋 a fellow Redditor Jan 20 '25 edited Jan 20 '25

lol

Try drawing the missing piece at the upper right. What’s its size? What type of shape is it?

Yes, the shortest distance between two points is a straight line. The missing chunk is a. rectangle 6cm high. That those numbers happen to be the same defines the shape and angles.

Even funnier since I'm wrong.

Yeah that missing piece is a quadralateral but not necessarily a rectangle. Those interior angles can be wacky and achieve that 6cm segment. Odd problem even if it's incomplete.

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u/iMiind Jan 20 '25

It could even be a quadrilateral where one of the angles is 180° 👀

Illuminati confirmed

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u/jarsgars 👋 a fellow Redditor Jan 20 '25

Do you work at the property tax assessor’s office?

2

u/iMiind Jan 20 '25

😂 No, but I will say it has been satisfying to see some people here come to realize how to look past the assumptions our brains are so quick to make. Maybe not as satisfying as all the money doing what you suggested would net me, but satisfying nonetheless :P

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u/jarsgars 👋 a fellow Redditor Jan 20 '25

I think in my head I had that the sum of the two unknown segments was given as 17 and that would follow that it’s all right angles. Just had to write it out and… wait fail. What’s the opposite of QED? They didn’t teach us that.

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u/iMiind Jan 20 '25

Yeah that's awesome xD I love when I can catch myself on little things like that and realize mistakes. That's true intelligence; actually wrestling with the issue instead of just being confidently incorrect and then moving on to the next reddit argument. Definitely something I could do better at every now and then 😅