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View Poll Results: 48÷2(9+3) = ????
2
30
54.55%
288
25
45.45%
Voters: 55. You may not vote on this poll

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Old Apr 8, 2011 | 05:33 PM
  #101  
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jeffjones: you should ask for your money back...

48/2(9+3) if you want to distribute the 2 you have to distribute the 48/2 = (216+72) = 288

its like if you had xy(9+3) it does not equal x/(9x+3x); just remember * an / have same importance so you work left to right if there is a x*z/y = xz/y not x(z/y)
 
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Old Apr 8, 2011 | 05:42 PM
  #102  
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Originally Posted by jp_greenville13
You're missing the point! You are using a false property to solve the equation. You can't do that and expect a correct answer. If the property was not false it could be applied without changing the answer or the order of operations.
How is it a false property?
you can't add symbols and change the equation and expect a correct answer.
the 2 is distributed between both the 9 and the 3.
thats what 2(9+3) means regardless you have to simplify that before you can do anything which is:

2(9+3)
=(18+6)
=24

The only way to do it the other way to get 288 is add a bracket (48/2)
or remove the distributive law from the question and add a multiplication.
If I didn't take years of univerisity math I would be saying it was 288 as well.
But the whole problem is no mathematician would ever write a equation in this format.
 
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Old Apr 8, 2011 | 05:47 PM
  #103  
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Originally Posted by jeffjones
How is it a false property?
you can't add symbols and change the equation and expect a correct answer.
the 2 is distributed between both the 9 and the 3.
thats what 2(9+3) means regardless you have to simplify that before you can do anything which is:

2(9+3)
=(18+6)
=24

The only way to do it the other way to get 288 is add a bracket (48/2)
or remove the distributive law from the question and add a multiplication.
If I didn't take years of univerisity math I would be saying it was 288 as well.
But the whole problem is no mathematician would ever write a equation in this format.
I suck at math and said 2 to start with lol. I posted it on my algebra class board, lets see what all they get lol
 
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Old Apr 8, 2011 | 06:01 PM
  #104  
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Originally Posted by jp_greenville13
It's 2. You can't get x squared by dividing x by x.

so now you're doing the second multiplication BEFORE the division to the left? I'm confused.
 
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Old Apr 8, 2011 | 06:04 PM
  #105  
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Originally Posted by jeffjones
How is it a false property?
It's a false property in this instance because if you use it it changes the answer that you get by calculating it the way that it is written


Originally Posted by jeffjones
you can't add symbols and change the equation and expect a correct answer.
Parenthesis imply multiplication. Therefore
48/2(9+3)=48/2*(3+9)

This is not adding a symbol or changing the equation. It is simply showing a symbol that is not shown.

I would say I agree with blue devil that you should ask for your money back but you can't expect to be taught common sense for a price. If the tool doesn't fit then you can't use it (in this case the distributive property)

You can't use a 14 millimeter socket on a 12 millimeter fastener.

You can't use the distributive property on this equation.

They don't work.

Every other way you figure it out will lead to 288. If you can show me another way to solve this correctly that gives 2 as a result... Edit: without using the distributive property ........then I will eat my words.
 

Last edited by jp_greenville13; Apr 8, 2011 at 06:23 PM.
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Old Apr 8, 2011 | 06:07 PM
  #106  
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Originally Posted by bluedevil3758
jeffjones: you should ask for your money back...

48/2(9+3) if you want to distribute the 2 you have to distribute the 48/2 = (216+72) = 288

its like if you had xy(9+3) it does not equal x/(9x+3x); just remember * an / have same importance so you work left to right if there is a x*z/y = xz/y not x(z/y)
48
____
2(9+3)

=(216+72) ?

Pass that **** this way it must be good.

you are right about xy(9+3) = (9xy+3xy)

but the 48 doesn't have anything to do with the 2(9+3).
the 48 is the numerator and the 2(9+3) is the denominator as the original equation is written.
all your doing is taking the (9+3) from the denominator and putting it in the numerator for no reason?

because what your saying is the equation looks like this:

48*(9+3)
______ = 288
2

because that is the same as:

48
__ * (9+3) = 288
2
 
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Old Apr 8, 2011 | 06:09 PM
  #107  
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lol I tried, good luck to everyone ^^
 
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Old Apr 8, 2011 | 06:13 PM
  #108  
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Originally Posted by jp_greenville13
It's a false property in this instance because if you use it it changes the answer that you get by calculating it the way that it is written




Parenthesis imply multiplication. Therefore
48/2(9+3)=48/2*(3+9)

This is not adding a symbol or changing the equation. It is simply showing a symbol that is not shown.

I would say I agree with blue devil that you should ask for your money back but you can't expect to be taught common sense for a price. If the tool doesn't fit then you can't use it (in this case the distributive property)

You can't use a 14 millimeter socket on a 12 millimeter fastener.

You can't use the distributive property on this equation.

They don't work.

Every other way you figure it out will lead to 288. If you can show me another way to solve this correctly that gives 2 as a result then I will eat my words.

Ok I will substitute an x for the 2 in the equation and make the equation equal 2.

48 / x(9+3)=2
48 / 9x +3x=2
48 / 12x=2
48 / 2=12x
24=12x
24 /12 = x
2=x
 
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Old Apr 8, 2011 | 06:14 PM
  #109  
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Originally Posted by regener8ed
another question for all the "order of operations" fans:

4x ÷ 2x =

2x² or 2 ?



.
4x/2x = 2(1) = 2 = 2*x/x

Originally Posted by regener8ed
so now you're doing the second multiplication BEFORE the division to the left? I'm confused.
x/x=1 no matter how you look at it
 
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Old Apr 8, 2011 | 06:16 PM
  #110  
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Originally Posted by jeffjones
Ok I will substitute an x for the 2 in the equation and make the equation equal 2.

48 / x(9+3)=2
48 / 9x +3x=2
48 / 12x=2
48 / 2=12x
24=12x
24 /12 = x
2=x

You are STILL using the distributive property!!! which does not work for this equation! lol
 
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