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# What's the answer to this equation?

 View Poll Results: The answer is... 2 101 42.08% 288 139 57.92% Voters: 240. You may not vote on this poll

04-09-2011, 10:52 AM
#476
CrAzYNiNe
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Quote:
 Originally Posted by Railman His way would still be incorrect. 2a is merely a shortened form of 2×a. With a = 9+3 : 48÷2a = 24a = 24(9+3) = 288 The issue is with people assuming that what is in front of a bracket (or variable) is part of the bracket and must be treated with the bracket as a single entity (so to speak). It isn't.
I don't agree. 2a is not the same as 2*a. We may treat it like 2*a, but 2a should stay together and not be broken up by any operator.

04-09-2011, 10:55 AM
#477
tigidou
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Quote:
 Originally Posted by Railman His way would still be incorrect. 2a is merely a shortened form of 2×a. With a = 9+3 : 48÷2a = 24a = 24(9+3) = 288 The issue is with people assuming that what is in front of a bracket (or variable) is part of the bracket and must be treated with the bracket as a single entity (so to speak). It isn't.

Very good and you are right, I'm glad you corrected me.. Algebra (by calculating it right) actually proves its 288..

48/2a = 24a = 24(9+3) = 288.

thanks!

Still, it seems that this is a matter of convention and that not EVERYONE in the field agrees.

04-09-2011, 10:59 AM
#478
Montreal Typical
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Quote:
 Originally Posted by CrAzYNiNe I don't agree. 2a is not the same as 2*a. We may treat it like 2*a, but 2a should stay together and not be broken up by any operator.
Whether you agree is irrelevant. It is what it is.

You can take out multiplication symbols before variables or brackets, but they're still there.

04-09-2011, 11:12 AM
#479
Frankenheimer
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Quote:
 Originally Posted by HeShootsHeScores lol at this pic

By the way : 2

04-09-2011, 11:29 AM
#480
CrAzYNiNe
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Quote:
 Originally Posted by tigidou Very good and you are right, I'm glad you corrected me.. Algebra (by calculating it right) actually proves its 288.. 48/2a = 24a = 24(9+3) = 288. thanks! Still, it seems that this is a matter of convention and that not EVERYONE in the field agrees.
Really?

48
2a

That wouldn't simplify to
24
a

??? Really?

04-09-2011, 11:32 AM
#481
Montreal Typical
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Quote:
 Originally Posted by CrAzYNiNe Really? 48 2a That wouldn't simplify to 24 a ??? Really?
Your mistake is seeing 2a as a single entity.

You are not dividing by (2a) but by 2 then multiplying by a.

48÷2a != 48÷(2a)

04-09-2011, 11:47 AM
#482
tigidou
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Quote:
 Originally Posted by Railman Your mistake is seeing 2a as a single entity. You are not dividing by (2a) but by 2 then multiplying by a. 48÷2a != 48÷(2a)

Railman, I agree with you, BUT still this is not even being agreed on in the math field (from what I understand).

If you take several Texas Instruments (different models), you'll see that they don't handle it the same. This is a convention which not everyone agrees...

 04-09-2011, 01:04 PM #483 XperHFB   Join Date: Apr 2010 Posts: 573 vCash: 500 2 is the answer
04-09-2011, 01:06 PM
#484
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Quote:
 Originally Posted by Railman Your mistake is seeing 2a as a single entity. You are not dividing by (2a) but by 2 then multiplying by a. 48÷2a != 48÷(2a)
if you do not put the sign you assume its a single entity
-end of line.

 04-09-2011, 03:27 PM #485 LyricalLyricist Registered User   Join Date: Aug 2007 Location: Montreal Country: Posts: 23,196 vCash: 500 Not for anything, but I got 2, and it's likely 288. I say likely cuz it's absolutely irrelevant. When you do higher math no one uses elementary symbols. They use fractions. You would either see: 48 2(9+3) 48*(9+3) 2 This is all a pointless pissing match, because no one will ever ask you a question of the original format unless you work in an elementary school. The only place I can imagine this being an issue is for those in programming as you're forced to use / or the divide symbol, but even then, you use brackets.
 04-09-2011, 03:59 PM #486 Bieber fever Registered User     Join Date: Mar 2010 Location: Westmount Posts: 5,559 vCash: 500 oh god this again ? the correct answer is 2. When you don't put a sign of multiplication there is a general concusses ( not a official rule ) that it implied a bracket. so : 48÷2(9+3) = 48÷[2(9+3)] = 2 But 48÷2X(9+3) =288 simple as that...
 04-09-2011, 04:21 PM #487 HabsNation514 Registered User   Join Date: Jan 2011 Posts: 107 vCash: 500 Wait a sec...I got...WHO THE HE!! CARES??
04-09-2011, 04:24 PM
#488
CrAzYNiNe
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Quote:
 Originally Posted by HabsNation514 Wait a sec...I got...WHO THE HE!! CARES??
people like myself and others who uses math everyday, whether school, or career. We all would like to know.

 04-09-2011, 04:29 PM #489 Ginu Registered User     Join Date: Feb 2009 Posts: 3,900 vCash: 500 I have a PhD in Communications Engineering. 48/2a != 48/(2a) 48/2a means 48 is divided by 2 and the result is multiplied by a. There IS a convention that, if 2a is a single quantity, then it will be written as 48/(2a). Math is not built on the foundation of ambiguity. There are strict rules that have to be followed. If things were so willy nilly, we'd see all technology self-destruct randomly all over the world. Math is the basis for everything. There are set ways that you do things.
 04-09-2011, 04:30 PM #490 Bieber fever Registered User     Join Date: Mar 2010 Location: Westmount Posts: 5,559 vCash: 500 to people who thinks it's 288 : xy÷xy= y^2 or xy÷xy=1
04-09-2011, 05:04 PM
#491
LyricalLyricist
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Quote:
 Originally Posted by hotsauce514 to people who thinks it's 288 : xy÷xy= y^2 or xy÷xy=1
They go with y^2. I would go for the second, but whatever.

04-09-2011, 05:19 PM
#492
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Quote:
 Originally Posted by hotsauce514 to people who thinks it's 288 : xy÷xy= y^2 or xy÷xy=1
There's a reason why algebra should be written on one line only. I this case it should be y^2.

04-09-2011, 05:20 PM
#493
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Quote:
 Originally Posted by hotsauce514 oh god this again ? the correct answer is 2. When you don't put a sign of multiplication there is a general concusses ( not a official rule ) that it implied a bracket. so : 48÷2(9+3) = 48÷[2(9+3)] = 2 But 48÷2X(9+3) =288 simple as that...
ummm no. When multiplying it is accepted practice to omit the operator. Even if it was a bracket, it would be a standalone bracket and would be solved by multiplying by 1 and you would still arrive at 288.

Your method would be 48/(2)(9+3). The answer to that is still 288. Under no circumstances does the 2 find its way into the bracket that contains 9+3.

 04-09-2011, 05:22 PM #494 pine*   Join Date: Feb 2008 Location: Montréal Country: Posts: 8,340 vCash: 500 xy÷xy= y^2 (xy)÷(xy)= 1 ... damn you misc, damn you.
 04-09-2011, 05:28 PM #495 DDs not undersized Former Partisan duCH     Join Date: Jan 2007 Location: Bangkok Country: Posts: 3,404 vCash: 500 Does this thread means we are finally allowed to start a non hockey related thread? I wanted a thread about the federal elections. Go Bloc Québécois Go!! Or Go (anything but Harper) Go!
04-09-2011, 05:28 PM
#496
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Quote:
 Originally Posted by WTFpineapple xy÷xy= y^2 (xy)÷(xy)= 1 ... damn you misc, damn you.
to me they should both be 1, what is the rational for y^2?

04-09-2011, 05:30 PM
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Quote:
 Originally Posted by Fish on The Sand to me they should both be 1, what is the rational for y^2?
x*y/x*y = x/x*y*y = y^2

04-09-2011, 05:32 PM
#498
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Quote:
 Originally Posted by Fish on The Sand to me they should both be 1, what is the rational for y^2?
standard order of operations.

xy÷xy= y^2
-------------
x*y= xy
x*y÷x=y
y*y= y^2

04-09-2011, 05:41 PM
#499
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Quote:
 Originally Posted by WTFpineapple xy÷xy= y^2 (xy)÷(xy)= 1 ... damn you misc, damn you.
simple clear not ambigious

But i read about the possibility of the answer 2. Yes it is possible, but its the lazy way.
some people made a convention so they do not put * or (). as a software engineer who always work with TI voyage 200, I'm happy that you need to put bracket (if more than 1 item)to make it Clear.

That way, you are sure that you are not doing wrong. Everyone will understand.
Those who took 2 and rejected 288, hope your not working on critical systems (laser treatment, medicinal machines...) hope you dont omit brackets

100% of the people must agree that the answer CAN be 288 with the BEMDAS rule (well documented), vs the value 2.
the value 2, I saw no rule or link explaining.

1 tried to explain. but he said, "(And please do not send me an e-mail either asking for or else proffering a definitive verdict on this issue. As far as I know, there is no such final verdict. And telling me to do this your way will not solve the issue!)".
http://www.purplemath.com/modules/orderops2.htm

IMO, its only some lazy anarchist that created this "rule"

04-09-2011, 05:52 PM
#500
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Quote:
 Originally Posted by Fish on The Sand ummm no. When multiplying it is accepted practice to omit the operator. Even if it was a bracket, it would be a standalone bracket and would be solved by multiplying by 1 and you would still arrive at 288. Your method would be 48/(2)(9+3). The answer to that is still 288. Under no circumstances does the 2 find its way into the bracket that contains 9+3.
Please could you give me the reference of where you found that it is standard practice to omit the operator. Have you considered multiplication by juxtaposition. What do you mean by saying the 2 does not find it's way into the bracket?

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