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#1 rookie1ja

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Posted 31 March 2007 - 03:06 PM

Key - Back to the Matchstick Puzzles
1. Move four matches so that three squares are created.
2. Move three matches so that two rectangles are created.
3. Move two matches so that two rectangles are created.
key.gif

This old topic is locked since it was answered many times. You can check solution in the Spoiler below.
Pls visit New Puzzles section to see always fresh brain teasers.


Spoiler for Solution

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#2 vinay0007

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Posted 14 May 2007 - 09:56 AM

in the 3rd figure, there is only one is rectangle and the other one is rhombus..
[url:b38a7]http://en.wikipedia.org/wiki/Rectangle[/url]
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#3 rookie1ja

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Posted 14 May 2007 - 11:24 AM

in the 3rd figure, there is only one is rectangle and the other one is rhombus..
[url:e2cea]http://en.wikipedia.org/wiki/Rectangle[/url]


The other one should be a square (which is a rectangle as well), maybe not looking as one since I drew it without a ruler.
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#4 fosley

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Posted 15 May 2007 - 04:20 PM

It's not a perfect square. The upper-left and lower-right sides form the hypotenuse of a 43 x 43 x ~61 pixel triangle, while the upper-right and lower-left sides form the hypotenuse of a 46 x 46 x ~63 pixel triangle. However, I'd say that's close enough for a hand drawing that's just meant to show the idea. Also, there are technically gaps between the matches and the edges don't perfectly line up. But if you discount that, it's a rhombus, square and rectangle as well as others:

-- If you draw straight lines along the outside edges of the matches (or the inside edges, or the centerlines):
1. It's a polygon because it's a closed area with straight lines as boundaries
2. It's convex because no interior angles are greater than 180°
3. It's a quadrilateral because it's a polygon with 4 sides
4. It's a parallelogram because it's a quadrilateral and opposing sides are parallel
5. It's a rectangle because it's a parallelogram and all adjacent sides form right angles
-- If you discount the 2 pixel difference in side lengths:
6. It's a rhombus because it's a parallelogram and all sides are equal length
7. It's a square because it's a rectangle and a rhombus
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#5 wadupwitdat_nothin

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Posted 30 July 2007 - 06:00 PM

It's not a perfect square. The upper-left and lower-right sides form the hypotenuse of a 43 x 43 x ~61 pixel triangle, while the upper-right and lower-left sides form the hypotenuse of a 46 x 46 x ~63 pixel triangle. However, I'd say that's close enough for a hand drawing that's just meant to show the idea. Also, there are technically gaps between the matches and the edges don't perfectly line up. But if you discount that, it's a rhombus, square and rectangle as well as others:

-- If you draw straight lines along the outside edges of the matches (or the inside edges, or the centerlines):
1. It's a polygon because it's a closed area with straight lines as boundaries
2. It's convex because no interior angles are greater than 180°
3. It's a quadrilateral because it's a polygon with 4 sides
4. It's a parallelogram because it's a quadrilateral and opposing sides are parallel
5. It's a rectangle because it's a parallelogram and all adjacent sides form right angles
-- If you discount the 2 pixel difference in side lengths:
6. It's a rhombus because it's a parallelogram and all sides are equal length
7. It's a square because it's a rectangle and a rhombus


STOP YOU MAKE MY BRAIN HURT!!!!!!!!!! AAAAAAAAHHHHHHHHHH!!!
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#6 jayp

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Posted 18 October 2007 - 04:40 AM

So, Fosley, you're kind of an idiot, huh? Since the matchsticks in the image don't form a perfect square to the pixel we must assume it's on purpose, correct? It couldn't possibly be a forgiveable offense by an author who assumed their readers would have the common sense to recognize the puzzle was a brain teaser, not an exercise in 6th grade math, right? In fact... come to think of it... since we're not assuming anything here... what gives - we weren't provided with an equation for shaping the head of the match in two dimensions - let alone three (everyone knows a real match couldn't possibly exist in only two dimensions)! Crazy! And, wait, are we to assume that the shaft of a matchstick is perfectly straight and true? No curvature? I mean, it would be completely reasonable to assume at least a 2-3% deflection in poor quality wood, right? I mean - go to Lowes and check out a typical 2x4! Them things are like bent in half, goshdarnit (I "spoke" like a hick there on purpose, grammar nazis)! But wait! What kind of matches are these?!? They might be from a matchbook and thus not possessing a wooden shaft! It might be cardboard! In which case, we have to wonder if they're placed with their longest side parallel to the surface or perpendicular (as viewed from either end of the match, you little technical bugger, you)! And are all of the matches arranged with a similar orientation to the surface? Certainly having some placed perpendicular and others parallel would present a whole slew of challenges in the third dimension (see previous matchhead curvature questions). But wait, you said it was a matchbook? So was the matchbook in my back or front pocket when I sat down before arranging the puzzle? That would certainly impact the curvature! I'm not a portly fellow, but I can bend a cardboard match with the best of 'em when I sit on it!

This is all so confusing! I wish I could safely assume that all matches were uniform, not drawn to scale, and offered as a representative figure aiding in a simple exercise to pass the time somewhere between your 9th and 14th beer!

At some point you'll realize the real brilliant kids are the ones who can hide the nerdy questions deep down inside (where they belong 97% of the time) and function like normal people, when necessary, instead of trying to induce respect by spouting bullsh*t.
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#7 darempf

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Posted 09 November 2007 - 08:06 PM

*laughing hysterically* Well done.
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#8 PlayTheMindGame

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Posted 17 November 2007 - 10:51 PM

That was pretty well said Jayp.
XD
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#9 BeerGoddess

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Posted 23 February 2008 - 03:51 AM

That was pretty well said Jayp.
XD

Hey, Fosley, have you looked at the matchstick cow yet? Maybe you shouldn't... you might be up all night with those old text books of yours.
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#10 cramer

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Posted 03 March 2008 - 08:25 AM

Here's another way to do the first one

matchsticks.GIF

Edited by cramer, 03 March 2008 - 08:27 AM.

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