Is there a standard way of labeling shapes?

silverpuma · 2011-06-23 07:00:02

A bit of a strange question here, but that's nothing unusual for me:

I have attached a screenshot of a book I'm going through and I was wondering if there is a standard way to specific your answers when dealing with angles and shapes. The image "should" explain what I mean and thanks for taking the time to look.............

anonimnystefy · 2011-06-23 07:24:07

hi silverpuma

labeling lines and angles usually doesn't require anything strict.It only matters in similarity,homothety,isometric transgormations and such,because you have to know which point is a picture of which,and also if Δ ABC~ Δ CDE then it is usually understood that Δ ABC is not similar to Δ CED or DCE or DEC or ECD or EDC.

Also for labeling geometric shapes every two adjacent letters are the name of an edge of that shape.So if you have a rectangle ABCD it's the same as having ADCB or BCDA or BADC and so on...

hope this helps.

silverpuma · 2011-06-23 07:43:38

anonimnystefy wrote:

hi silverpuma
labeling lines and angles usually doesn't require anything strict.It only matters in similarity,homothety,isometric transgormations and such,because you have to know which point is a picture of which,and also if Δ ABC~ Δ CDE then it is usually understood that Δ ABC is not similar to Δ CED or DCE or DEC or ECD or EDC.
Also for labeling geometric shapes every two adjacent letters are the name of an edge of that shape.So if you have a rectangle ABCD it's the same as having ADCB or BCDA or BADC and so on...
hope this helps.

Thanks for that, as I a bit worried I could be marked as wrong just because my labeling was not the "standard" way, even for something as simple as the 4 corners on a square. Did I need to begin with my A at the bottom right and go clockwise or the top left and go anti closkwise etc etc. Thanks for your patience with me anonimnystefy

anonimnystefy · 2011-06-23 07:53:52

hi silverpuma

don't mention it.glad i could help.what level are you on?

silverpuma · 2011-06-23 09:47:45

anonimnystefy wrote:

hi silverpuma
don't mention it.glad i could help.what level are you on?

This is from my guestbook post...............

I'm a mature student aged 52 left school with zero qualifications. But am now just beginning to teach myself GCSE Maths. This has grown out of helping my 10 yr son with his maths as he prepares for the equivalent of the old 11+/transfer exam (I'm from N Ireland). I'm amazed how much I love exploring this new world of numbers. For my leisure and bedtime reading its now prime Factors or negative numbers instead of, well anything rather than maths....!! I "think" I may have reasonably good but basic numeracy skills (began and ran 3 successful business etc).

I'm beginning at 10-11 year old level to make sure I have the foundation correct and then move swiftly to GCSE maths level. I'll be learning at home so I need to teach myself through helps and books and website etc. So I have a number of websites saved of the video and text varieties and this is the one I come back to all the time. Your clear explanations are wonderful. So from a grateful old codger like me please accept my appreciation :-)

anonimnystefy · 2011-06-24 07:28:58

hi silverpuma

do you know about Wolfram MathWorld:
http://mathworld.wolfram.com/

Last edited by anonimnystefy (2011-06-24 07:29:19)

silverpuma · 2011-06-24 07:57:37

Thanks for this I'll check it out.

I just spent an hour learning about angles and found it really fascinating ...............can't wait to begin Trigonometry.

anonimnystefy · 2011-06-24 08:36:16

hi silverpuma

i really like trigonometry.it is very cool but i have little problems with remembering formulas such as this one:
sin(a+b)=sinacosb+sinbcosa

silverpuma · 2011-06-24 09:52:23

anonimnystefy wrote:

hi silverpuma
i really like trigonometry.it is very cool but i have little problems with remembering formulas such as this one:
sin(a+b)=sinacosb+sinbcosa

I think Sculley out of the X-files will be looking for the author of that strange language....LOL Seriously though I can't resist sneaking a looking at some trig lessons, but I have a long way to go! I have enough trouble remembering supplementary and complimentary angles without all the sin stuff

Math Is Fun Forum

#1 2011-06-23 07:00:02

Is there a standard way of labeling shapes?

#2 2011-06-23 07:24:07

Re: Is there a standard way of labeling shapes?

#3 2011-06-23 07:43:38

Re: Is there a standard way of labeling shapes?

#4 2011-06-23 07:53:52

Re: Is there a standard way of labeling shapes?

#5 2011-06-23 09:47:45

Re: Is there a standard way of labeling shapes?

#6 2011-06-24 07:28:58

Re: Is there a standard way of labeling shapes?

#7 2011-06-24 07:57:37

Re: Is there a standard way of labeling shapes?

#8 2011-06-24 08:36:16

Re: Is there a standard way of labeling shapes?

#9 2011-06-24 09:52:23

Re: Is there a standard way of labeling shapes?

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