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#1 2015-06-06 01:57:32

Motimele
Guest

Mathematics: Triangles

Hello, please help me with the following.

•If you have two line A and B were 7 units and 9 units respectively. How many triangles can you form if A and B are joined together and the third side is a positive integer?

Thanks in advance.

#2 2015-06-06 02:58:17

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

Re: Mathematics: Triangles

Hi;


In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

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#3 2015-06-06 20:32:32

Bob
Administrator
Registered: 2010-06-20
Posts: 10,053

Re: Mathematics: Triangles

hi Motimele

Welcome to the forum.

q7hKCVx.gif

Imagine the two sides linked together by a hinge so a variety of triangles can be made by swinging the 7 around and joining up to make the third side.

Consider the extreme cases.  When the 7 and 9 form a line straight line the 'third side' is 16.  Because this is not a triangle the third side must be less than 16. (You couldn't have the third side any longer because the lines would not join up.)

When the 7 and 9 form an overlapping straight line the 'third side' is 2.  So the third side must be greater than 2.  (You cannot get the free ends to be any closer together.)

So possible lengths are 2 < third side < 16

Bob


Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob smile

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#4 2015-06-07 02:13:35

phrontister
Real Member
From: The Land of Tomorrow
Registered: 2009-07-12
Posts: 4,810

Re: Mathematics: Triangles




Here is a link to a video of the construction sequence of the drawing.



ZKWxBbi.png

Last edited by phrontister (2017-02-23 17:06:55)


"The good news about computers is that they do what you tell them to do. The bad news is that they do what you tell them to do." - Ted Nelson

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#5 2015-06-07 20:32:31

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

Re: Mathematics: Triangles

Hi;

Pretty use of Gebra!


In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

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#6 2015-06-07 21:31:28

phrontister
Real Member
From: The Land of Tomorrow
Registered: 2009-07-12
Posts: 4,810

Re: Mathematics: Triangles

But not quite as pretty as these shots taken of the Sydney Opera House during 'Vivid Sydney', and after which my Gebra drawing is modelled...as you can see.

efEqhwx.png

Last edited by phrontister (2017-02-23 17:08:02)


"The good news about computers is that they do what you tell them to do. The bad news is that they do what you tell them to do." - Ted Nelson

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#7 2015-06-07 22:18:16

Bob
Administrator
Registered: 2010-06-20
Posts: 10,053

Re: Mathematics: Triangles

hi phrontister

Yes, both very pretty.  Makes me want to go there.

phrontister wrote:

after which my Gebra drawing is modelled

Are you sure it wasn't the other way round ?  Seems like the guy who designed the Opera House had a glimpse of the future, saw your post, and got to work drawing the plans.  Why else make it that shape ?  What you need is to get hold of the time machine and then you can go back and claim royalties.  Hmmm.  Come to think of it, if you have the time machine, you might as well just find out who's going to win at Royal Ascot.

smile

Bob


Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob smile

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#8 2015-06-07 23:15:56

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

Re: Mathematics: Triangles

Hi;

Vivid Sydney caused a 71 percent drop in my vitamin A levels.


In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

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#9 2015-06-08 01:43:42

phrontister
Real Member
From: The Land of Tomorrow
Registered: 2009-07-12
Posts: 4,810

Re: Mathematics: Triangles

bobbym wrote:

Vivid Sydney caused a 71 percent drop in my vitamin A levels.

You sure that wasn't caused by staring at Cream's Disraeli Gears album cover too intensely, trying to work out if it contained a subliminal message?

Last edited by phrontister (2017-04-30 13:34:39)


"The good news about computers is that they do what you tell them to do. The bad news is that they do what you tell them to do." - Ted Nelson

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#10 2015-06-08 02:56:41

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

Re: Mathematics: Triangles

I have not seen that album. I was looking at Bob's Ascot link though. Loved the way those people are attired, very nice.


In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

Offline

#11 2015-06-08 03:07:57

phrontister
Real Member
From: The Land of Tomorrow
Registered: 2009-07-12
Posts: 4,810

Re: Mathematics: Triangles

Hi Bob,

Unfortunately the time machine is no more: I destroyed it here.

If only I could travel back in time to a preposthumous since-departed-time-machine time, I would then use the knowledge I now know to preserve it for the benefit of mankind (in particular, you @ Ascot, and me, with those design royalties...although I'm not certain that I'd get all that much, given that my piccy is in the public domain).

But, alas...'tis gone! sad >sniff<

Hi Bobby,

I changed my previous post to include a link to the album on youtube.


"The good news about computers is that they do what you tell them to do. The bad news is that they do what you tell them to do." - Ted Nelson

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#12 2015-06-08 19:34:27

Bob
Administrator
Registered: 2010-06-20
Posts: 10,053

Re: Mathematics: Triangles

phrontister wrote:

I go to Australia (Land of Tomorrow) and destroy the time machine. The cheese is safely mine there, for, "tomorrow never comes".

I'm not convinced the time machine is truly gone 'at this time'.

Firstly, did you actually get to the Land of Tomorrow, if tomorrow never comes.  Surely Tomorrow has to be present in order for you to go there.  Secondly, if we assume you did destroy it tomorrow, that suggests it is not destroyed today.  So maybe it still exists.

There is also a simple way to re-invent it.

(1) Examine the time machine to learn how it works.

(2) Use this information to build a time machine.

(3) Use this time machine to take the time machine back to a moment before (1) so that you can do the algorithm from step (1).

Bob


Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob smile

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#13 2015-06-09 02:13:55

phrontister
Real Member
From: The Land of Tomorrow
Registered: 2009-07-12
Posts: 4,810

Re: Mathematics: Triangles

Hi Bob,

Firstly, did you actually get to the Land of Tomorrow…

Yes…I have documentation proving that I'm an Australian living in Australia, and the GPS I'm holding confirms that I am, in fact, located in Australia (not that I ever doubted it).

…if tomorrow never comes.

The question of how I could have arrived here 'tomorrow' has me stumped. All I remember about the journey is that I embarked on the trip to The Land of Tomorrow in the then-present 'today', fell asleep along the way, and woke up in Australia 'tomorrow'. I've always regretted taking that nap, as I missed out on the experience of a lifetime when time changed from 'today' to 'tomorrow'.

Examine the time machine to learn how it works.

Not possible: I really did destroy it, sold the mangled wreck to a scrap metal merchant just a few stone's-throws from where I live, and bought a treadly with the $$. I fondly recall the tm with each km I pedal.

Secondly, if we assume you did destroy it tomorrow, that suggests it is not destroyed today.  So maybe it still exists.

Maybe it does: but not undestroyed, today, here, in The Land of Tomorrow. The only possible place it could exist undestroyed, today, is elsewhere: eg, where you are. Could you try and find it for me? And if you do happen to find it, you can keep it if you like (if anyone challenges your ownership of it, just refer them to this post).

xnyw3qi.jpg

Last edited by phrontister (2017-02-27 00:38:43)


"The good news about computers is that they do what you tell them to do. The bad news is that they do what you tell them to do." - Ted Nelson

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#14 2015-06-09 04:18:04

phrontister
Real Member
From: The Land of Tomorrow
Registered: 2009-07-12
Posts: 4,810

Re: Mathematics: Triangles

Hi;

I've included a link on post #4 to a video of the drawing's construction sequence.


"The good news about computers is that they do what you tell them to do. The bad news is that they do what you tell them to do." - Ted Nelson

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