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#1051 Help Me ! » Congruency and Similarity » 2007-05-16 00:27:56
- Identity
- Replies: 2
I reckon this is a pretty ambiguous topic... all those definitions (SSS, SAS, ASA, RHS, PPP, PAP, APA, AA) could be interchanged for one another given sufficient information on the triangle.
Well basically check out triangle 1. Definition SAS states 'two sides plus the INCLUDED angle'... But if you think about, you can conclude, can you not, that both these triangles are congruent?
Likewise, triangle 2: ASA states 'two angles plus the INCLUDED side'... yet, these triangle look similar, even if they do not follow that rule to the word?
For diagram3, the book states blatantly that the triangles are NOT CONGRUENT. However, shouldn't that answer really be: It cannot be proved whether or not these triangles are congruent?
When finding the correct ratios in similar triangles, how do you know which side to divide by which? Say in ABC, AB = 4, AC = 8, BC = 6 and in EFG, EF = 6, EG = 12, FG = 9. Should you always do biggest in ABC over biggest in EFG, smallest in ABC over smallest in EFG, and the remaining side over the remaining side?
Also, one last thing for this post... ~ means similar to, ~ (with line through it) means not similar to. Can the (with line through it) thing also be applied to congruency? What is the symbol for not congruent
thanks for help
#1052 Re: Introductions » Know what? » 2007-05-16 00:03:05
Random indeed! Welcome Lulu!
#1053 Re: Help Me ! » Triangle Problem » 2007-05-14 02:26:34
Hey I just realised an easier way!
AD = DC (isosceles triangle ADC)
1−x² = x
x²+x-1=0
#1054 Re: Dark Discussions at Cafe Infinity » Why is power such an addiction? » 2007-05-14 01:36:40
Is it possible to describe a craving for power in terms of the fundamentals that we are familiar with?
Would I be right in saying:
A great number of revolutionaries went on to become dictators because during the revolution they got power through leadership, saw what it could bring them, and naturally wanted more. Soon, the dictators had so much power, that more would be meaningless, since they could already buy every luxury they desired, and yet they still yearned for more power because they were already addicted to it.
It's pretty confusing really, because in many cases power is sought not for luxuries, but merely for ... more power.
The party seeks power entirely for its own sake. We are not interested in the good of others; we are interested solely in power. Not wealth or luxury or long life or happiness: only power, pure power. - 1984
#1055 Re: Jokes » good jokes which everybodys probably heard » 2007-05-14 01:30:34
They're pretty good XD, the first time I heard the third one was during chapel though, and not intended as a joke o_O meh
#1056 Re: Help Me ! » I need tips... » 2007-05-13 23:16:01
Well, I kinda figured it was too time consuming to do what I did last post, so here is a file containing all the papers!
Behold!
http://www.megaupload.com/?d=7DI2J73Y
#1057 Re: Jokes » This is a true story » 2007-05-13 23:01:47
Lol, I actually believed most of it, until the part when you tried to squeeze through 
#1058 Re: This is Cool » 9,8,0,1 » 2007-05-13 01:44:51
I haven't checked to see if this one is in there, but check this out
11^0 = 1
11^1 = 11
11^2 = 121
11^3 = 1331
11^4 = 14641
Pascal's triangle! Or... at least that's what my math teacher told me... After 11^4 its gets a bit weird.
#1059 Dark Discussions at Cafe Infinity » Why is power such an addiction? » 2007-05-13 00:26:50
- Identity
- Replies: 13
I was preparing a powerpoint presentation on George Orwell's 1984, when it occurred to me that I couldn't understand - let alone explain - why people were addicted to power! You see, 1984 is a book about a dystopian society ruled by a dictator (Big Brother), who gained power after a revolution against capitalism, and the particular quote I had to answer to was a quote by Winston Smith, the protagonist of the novel: "I understand HOW, I do not understand WHY."
Why power? Why do some people aim for something like that, and in the process, knowingly destroy the lives of millions of others and make the world a horrible place? Is this kind of power only for psychopaths?
#1060 Re: Jokes » Another riddle slash thing » 2007-05-12 21:16:29
But you never provided any clues that you were driving the bus ???
#1061 Re: Puzzles and Games » Some New Puzzles on the Website » 2007-05-12 16:11:45
They're pretty cool! I wonder if I found a problem with the 'where did the extra dollar come from?' problem. At the start it says 2 friends eat, but 3 friends pay... was that a typo or intentional?
#1062 Re: This is Cool » The Classic Slide Rule » 2007-05-12 15:55:33
Man... I gotta say, this slide rule thing is amazing! I wish I had one! How much did you buy yours for??? Do you think they would be allowed in 'non-calculator' tests? MWAHAHAHAHAHAHH!!!!!....
#1063 Re: This is Cool » 9,8,0,1 » 2007-05-12 15:50:06
I wonder if you might be interested in this index of arithmetical tricks:
http://mathforum.org/k12/mathtips/beatcalc.html
You might find your own in there
#1064 Re: Dark Discussions at Cafe Infinity » Share Your Hobbies » 2007-05-10 01:42:50
Maths, Physics, Creating flash animations!, piano, and more recently naruto!
#1065 Help Me ! » Triangle Problem » 2007-05-09 23:18:41
- Identity
- Replies: 2
The problem is attached, the problem I'm having is I can get up to:
, but I don't know the length of CD =[.#1066 Re: Help Me ! » Another quadratic prob. » 2007-05-09 22:48:00
Thanks
#1067 Help Me ! » Another quadratic prob. » 2007-05-09 22:35:11
- Identity
- Replies: 3
If x is a solution of
, find#1068 Help Me ! » Quartic!? » 2007-05-09 21:31:09
- Identity
- Replies: 2
Please show me how to solve
#1069 Re: Help Me ! » I need tips... » 2007-05-09 20:01:13
This is 1990. No calculators are permitted, although other geometrical aids are. Questions generally tend to get harder as you go through each section, and questions 1 through 10 should pose no significant challenge.
Oh, and bear in mind, the Intermediate Division is intended for grades 9 to 10.
#1070 Re: Puzzles and Games » Puzzle based on actual situation encountered in real life » 2007-05-08 03:44:56
Sorry for the misunderstanding! I suggested AMNB because I forgot that by the time you got to B the car would still be back at A!
#1071 Re: Help Me ! » I need tips... » 2007-05-08 03:39:29
I have some Australian Maths Competition papers... every one from 1978 to 2005. Am I allowed to post them here...? The website I got them from is a school website, so you won't be able to access it.
#1072 Re: Puzzles and Games » Puzzle based on actual situation encountered in real life » 2007-05-07 01:24:44
Why can't you simply go AMNB if you can walk from door to door?
#1073 Re: Help Me ! » I need tips... » 2007-05-06 09:11:41
I assume it would be in the realm of problem solving, here are some tips if you get stuck... but it would be nice if you could specify:
Use a diagram, drawing or model
Make a list
Look for a pattern
Find a rule or formula
Try a simpler version of the problem
Use trial and error when needed (and refine if necessary)
Eliminate possibilities
Act it out
Work backwards (from a stage you know is correct)
Might sound simple, but easy to get frantic and forget.
#1074 Re: Euler Avenue » 0.99...=1 » 2007-05-05 01:00:16
If you have x < 1, then x =/= 0.999... ?
#1075 Re: Help Me ! » numbers of sequences we can do ! » 2007-05-05 00:30:05
Do you mean to say that 'x' is a constant which is multiplied by the numbers in the sequence?
If so, then inequality holds for all x ≥ 0.