Khan Academy Challenging Set of Exercises

Post Reply New Topic

Been working on the following set of exercises:

https://www.khanacademy.org/math/recrea ... -puzzles-2

And haven't got a clue of how to go about solving the first problem I have. Does anyone here have tips I could use? When is the right time to use Rotate, Reflect, or Dilate?

Can't do it on my iPad, I'll switch to my other computer and try it.

Cool. I hope you manage to succeed in figuring this out as this has me teased big time and I must know how it's done.

got the y right but the x wrong. still working on it. I'm doing the Dilation first. Going to try something different.

Any luck? I don't mean to put pressure on you, but you're my only hope thus far.

I've been working on it up until I went to bed yesterday, and I couldn't fall asleep last night because of that thing. I don't think it's un-solvable, but I'm struggling with it. I get the y axis, but not the x, or I get the x axis but not the y.

Have you worked on it?

Edited to add - I clicked on it just now and it's a different (polygon) puzzle. Solved it with:Reflection over the line from (7,7) to (-3,-3)
Rotation by 90° about (0,0).

Do you have a general system you use in trying to solve them? Or do you rely on luck?

I turn them around in my mind, so I guess the answer is luck mixed with visualization.

Here's something a little less tough, but still fun - it helps me unwind when I can't solve the more difficult puzzles. http://www3.amherst.edu/~nstarr/trom/puzzle-8by8/ -

Hi, alpineglow. I finally cracked the first one I was given. Which one were you struggling with?

If it was the same problem, here is what I did:

Dilate 2 around (0, 0).
Rotate 180 degrees.
Reflect.
Dilate back to normal (it should say 1/2).
Reflect.
Rotate 180 degrees.
Dilate 2.
Rotate 180 degrees.
Reflect.
Scale to half.

Cool that you solved it. (it makes me feel better that you did because once I have a puzzle in my brain it nags at me until it's solved.) I've been back to that link but it brings up a different polygon puzzle than the first one I saw. I'll go back there and try what you said works - hope I end up at the right puzzle though.

edited to add:
Whoa. It worked. I'll definitely sleep better now. How did you figure it out and how long did it take you if you don't mind?

You're stubborn like me then when it comes to puzzles and such.

How I managed to solve this one was basically a lot of trial and error, but there did come a point when the figure was somewhat "almost" matching the image that I thought that simply repeating the last few steps would do the trick. And it worked. Took me a few days to get it right.

There is one other problem that's trickier, though. And instead of using trial and error, what I did was code a program to help me solve the problem. When I finally got the code right, the program lagged a bit while running but eventually gave me the answer I was looking for. And so, if you're good with programming, you might want to use this as a method to solve any of the problems as well.

A couple of hints:

When you dilate, it should either be by 2 or by 1/2. Ignore all other numbers.

When you rotate, only focus on 90, 180, and 270.

I could've done it if I knew what I was trying to do.