48÷2(9+3)=?
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Summerstorm said:
Exactly what these two said folks. Not only is this a horrible math problem when it comes to putting it together, it's also the umpteenth time I've seen a thread like this on here just made to piss people off.Axolotl said:There is no correct answer. The whole BEDMAS or Order of Operations thing is primarily based on custom and is taught differently in different parts of the world. The question uses that to be ambiguous, it is not a "real" mathematical question so much as hook to try and start semantical arguements based on pointless mathematical principles that nobody above the age of 12 should be bothering with.
TLR It's a troll thread.
Some people's understanding of BIDMAS is shocking. When you take care of brackets, you do everything INSIDE the brackets. You don't expand them, you don't distribute them, you just do everything inside them. So you get:
48÷2(9+3) = 48÷2(12)
2(12) is EXACTLY THE SAME as 2x12. The brackets, at this point, are irrelevant. For people trying to subsitute x = 12 here, it doesn't work, as implied multiplication is a) ambiguous and b) works differently for variables.
48/2(9+x)=2
What you have done is distributed the 2 into the brackets. THIS IS INCORRECT. As this is multiplication, and not "part of the brackets", you have to do division and multiplication from left to right, as they have equal precedence. So rather than:
48/(18+2x)=2
you should have:
24(9+x)=2
216+24x = 2
24x = -214
x = -8.917
Which is not 3, obviously.
Despite your algebraic method, you are still falling for the trap that so many others are falling for, which is to assume that the 2 is part of the brackets, which is WRONG. Algebra does not make your answer more valid, especially when the core idea of the method, which happens to be what people have been trying to tell you is wrong, is completely overlooked.
48÷2(9+3) = 48÷2(12)
2(12) is EXACTLY THE SAME as 2x12. The brackets, at this point, are irrelevant. For people trying to subsitute x = 12 here, it doesn't work, as implied multiplication is a) ambiguous and b) works differently for variables.
No. You are completely missing the point of what everyone is saying. Even if you ignore the different rules for variables and constants, your maths is incorrect. Let's look at the first line:DaMullet said:Actually, I want to double check my work.
48/2(9+x)=2
48/(18+2x)=2
48=2(18+2x)
48=36+4x
48-36=4x
4x=12
x=3
Yup, still works.
/thread
48/2(9+x)=2
What you have done is distributed the 2 into the brackets. THIS IS INCORRECT. As this is multiplication, and not "part of the brackets", you have to do division and multiplication from left to right, as they have equal precedence. So rather than:
48/(18+2x)=2
you should have:
24(9+x)=2
216+24x = 2
24x = -214
x = -8.917
Which is not 3, obviously.
Despite your algebraic method, you are still falling for the trap that so many others are falling for, which is to assume that the 2 is part of the brackets, which is WRONG. Algebra does not make your answer more valid, especially when the core idea of the method, which happens to be what people have been trying to tell you is wrong, is completely overlooked.
2(x+y) does equal 2x+2y, of course. But 0.5*4(x+y) equals 2x+2y as well, right? Regardless how you write it. Could be 4*0.5(x+y). Like in the OP equation.InfiniteSingularity said:
What i am saying: Division by 2 EQUALS Multiplication by the half. I think this is pretty understandable. QED: 48/2(9+3) = 48*0.5*(9+3).
you couldn't accept the draw could you? very well then, in a mathematical equation, a coefficient is a constant by which a variable is multiplied. Hence there is a multiplication between the 2 and the (9+3)... Also why do i get the feeling i'm being trolled?The Unworthy Gentleman said:
Thomas, you're confusingThomas Rembrandt said:
A ÷ BC
= A * 1/BC
=A/BC
with
A ÷ B * C
=A * 1/B * C
=AC/B
Here 2 is the coefficient of the brackets so 48 is divided by the 2(9 + 3)
The 2 is a coefficient, it goes first. You can even process it before adding the 9 and the 3.
48 ÷ 2(9 + 3)
=48 ÷ (18 + 6)
=48 ÷ 24
=2
You're changing the equation by adding a multiplication operator.
No see you're just not getting it yes your answer is perfectly fine but if you go with order of operations you end up with 288. Regardless of how you see it in your mind this what you are doing and it is the same as think it is under a fraction line. Now you can quote me all you like after this I don't care but I refuse to add another post in the mountain of crap and epeen stroking that becomes every iteration of this thread.The Unworthy Gentleman said:
Last thing I will say is another pair of brackets are needed to rule out ambiguity. There are so many different ways of looking at the damn thing I can't believe people bite on this troll topic every damn time. For fuck sake is being right on the internet of all places so damn important? You people are making me a sad panda.
A coefficient is multiplied by a variable (i.e. (9+3) ). I don't understand where you learnt otherwise. Is that a new rule? "Coefficient goes first", that's nonsense. Multiplication and Division are equal and to be read left ro right.
I don't add anything to the equation just by adding a * . Do you think that coefficient has some magical abilities? There already is a multiplication going on, the convenient notation simply does not show them.
I don't add anything to the equation just by adding a * . Do you think that coefficient has some magical abilities? There already is a multiplication going on, the convenient notation simply does not show them.
So you're trying to tell me thatCerdog said:Some people's understanding of BIDMAS is shocking. When you take care of brackets, you do everything INSIDE the brackets. You don't expand them, you don't distribute them, you just do everything inside them. So you get:
48÷2(9+3) = 48÷2(12)
2(12) is EXACTLY THE SAME as 2x12. The brackets, at this point, are irrelevant. For people trying to subsitute x = 12 here, it doesn't work, as implied multiplication is a) ambiguous and b) works differently for variables.
No. You are completely missing the point of what everyone is saying. Even if you ignore the different rules for variables and constants, your maths is incorrect. Let's look at the first line:DaMullet said:Actually, I want to double check my work.
48/2(9+x)=2
48/(18+2x)=2
48=2(18+2x)
48=36+4x
48-36=4x
4x=12
x=3
Yup, still works.
/thread
48/2(9+x)=2
What you have done is distributed the 2 into the brackets. THIS IS INCORRECT. As this is multiplication, and not "part of the brackets", you have to do division and multiplication from left to right, as they have equal precedence. So rather than:
48/(18+2x)=2
you should have:
24(9+x)=2
216+24x = 2
24x = -214
x = -8.917
Which is not 3, obviously.
Despite your algebraic method, you are still falling for the trap that so many others are falling for, which is to assume that the 2 is part of the brackets, which is WRONG. Algebra does not make your answer more valid, especially when the core idea of the method, which happens to be what people have been trying to tell you is wrong, is completely overlooked.
.........AC
A ÷ BC = --
.........B
No.
If it were
A ÷ B * C
I might agree.
So what you're saying is that expanding brackets doesn't work...right? Because I'm pretty sure that's what you're saying.Cerdog said:Some people's understanding of BIDMAS is shocking. When you take care of brackets, you do everything INSIDE the brackets. You don't expand them, you don't distribute them, you just do everything inside them. So you get:
48÷2(9+3) = 48÷2(12)
2(12) is EXACTLY THE SAME as 2x12. The brackets, at this point, are irrelevant. For people trying to subsitute x = 12 here, it doesn't work, as implied multiplication is a) ambiguous and b) works differently for variables.
No. You are completely missing the point of what everyone is saying. Even if you ignore the different rules for variables and constants, your maths is incorrect. Let's look at the first line:DaMullet said:Actually, I want to double check my work.
48/2(9+x)=2
48/(18+2x)=2
48=2(18+2x)
48=36+4x
48-36=4x
4x=12
x=3
Yup, still works.
/thread
48/2(9+x)=2
What you have done is distributed the 2 into the brackets. THIS IS INCORRECT. As this is multiplication, and not "part of the brackets", you have to do division and multiplication from left to right, as they have equal precedence. So rather than:
48/(18+2x)=2
you should have:
24(9+x)=2
216+24x = 2
24x = -214
x = -8.917
Which is not 3, obviously.
Despite your algebraic method, you are still falling for the trap that so many others are falling for, which is to assume that the 2 is part of the brackets, which is WRONG. Algebra does not make your answer more valid, especially when the core idea of the method, which happens to be what people have been trying to tell you is wrong, is completely overlooked.
48/2(9+x)=2
Yes, when you have multiplication and division you read it left to right. But brackets trumps all. Why? Because that is the whole point of brackets. So you do solve the brackets first. And when you have a pronumeral in the brackets (WHICH INCLUDES THE COEFFICIENT) what do you do? You expand.
48/x(9+3)=2
48/9x+3x=2
48/12x=2
48=24x
2=x
x/2(9+3) = 2
x/24 = 2
x = 48
See, everytime I solved the brackets first. And I got 2 as the final result to OPs question. Because brackets comes before division and multiplication, and so when you have brackets like that you cannot read left to right.
With fractions you do not read left to right, or top to bottom - you solve whatever comes first.
IT IS THE SAME! What do you think BC means for gods sake. It means B*C. Where did you hear otherwise??ACman said:So you're trying to tell me thatCerdog said:Some people's understanding of BIDMAS is shocking. When you take care of brackets, you do everything INSIDE the brackets. You don't expand them, you don't distribute them, you just do everything inside them. So you get:
48÷2(9+3) = 48÷2(12)
2(12) is EXACTLY THE SAME as 2x12. The brackets, at this point, are irrelevant. For people trying to subsitute x = 12 here, it doesn't work, as implied multiplication is a) ambiguous and b) works differently for variables.
No. You are completely missing the point of what everyone is saying. Even if you ignore the different rules for variables and constants, your maths is incorrect. Let's look at the first line:DaMullet said:Actually, I want to double check my work.
48/2(9+x)=2
48/(18+2x)=2
48=2(18+2x)
48=36+4x
48-36=4x
4x=12
x=3
Yup, still works.
/thread
48/2(9+x)=2
What you have done is distributed the 2 into the brackets. THIS IS INCORRECT. As this is multiplication, and not "part of the brackets", you have to do division and multiplication from left to right, as they have equal precedence. So rather than:
48/(18+2x)=2
you should have:
24(9+x)=2
216+24x = 2
24x = -214
x = -8.917
Which is not 3, obviously.
Despite your algebraic method, you are still falling for the trap that so many others are falling for, which is to assume that the 2 is part of the brackets, which is WRONG. Algebra does not make your answer more valid, especially when the core idea of the method, which happens to be what people have been trying to tell you is wrong, is completely overlooked.
A ÷ BC
A
= -C
B
No.
If it were
A ÷ B * C
I might agree.
A/ BC
=
A
--- * C
B
or
1
--- * A * C
B
EDIT: FORMATATION was screwed up.
Multiplication and Division are equal, yes, and do read left to right. But Brackets are before both. So you expand brackets first.Thomas Rembrandt said:
Why do you expand brackets, rather than evaluate them? Because when there is ambiguity with the latter, the former is a proven consistent rule which will always work no matter what.
See thar be the dragons... or rather there lies your problem.InfiniteSingularity said:
You assume that 2(9+3) is single term. Assumptions are bad. Stop assuming. It's not one term.
48 is one term, 2 is other term (9+3) is third term. For 2(9+3) to be single term it has to be in brackets itself, that's what the brackets are for.
And yes. 48:2*12 = 48*12:2. Both return 288. Magick! You do not move anything from bottom to top however because you have no fractions here. If you want to write it as fraction you write it as
48
-- * (9+3) = 288
2
And as a final argument... Variables i choose you!
Solve x in:
48:2(x+3) = 2
and
48:2(x+3) = 288
No it isn'tThomas Rembrandt said:IT IS THE SAME! What do you think BC means for gods sake. It means B*C. Where did you hear otherwise??ACman said:So you're trying to tell me thatCerdog said:Some people's understanding of BIDMAS is shocking. When you take care of brackets, you do everything INSIDE the brackets. You don't expand them, you don't distribute them, you just do everything inside them. So you get:
48÷2(9+3) = 48÷2(12)
2(12) is EXACTLY THE SAME as 2x12. The brackets, at this point, are irrelevant. For people trying to subsitute x = 12 here, it doesn't work, as implied multiplication is a) ambiguous and b) works differently for variables.
No. You are completely missing the point of what everyone is saying. Even if you ignore the different rules for variables and constants, your maths is incorrect. Let's look at the first line:DaMullet said:Actually, I want to double check my work.
48/2(9+x)=2
48/(18+2x)=2
48=2(18+2x)
48=36+4x
48-36=4x
4x=12
x=3
Yup, still works.
/thread
48/2(9+x)=2
What you have done is distributed the 2 into the brackets. THIS IS INCORRECT. As this is multiplication, and not "part of the brackets", you have to do division and multiplication from left to right, as they have equal precedence. So rather than:
48/(18+2x)=2
you should have:
24(9+x)=2
216+24x = 2
24x = -214
x = -8.917
Which is not 3, obviously.
Despite your algebraic method, you are still falling for the trap that so many others are falling for, which is to assume that the 2 is part of the brackets, which is WRONG. Algebra does not make your answer more valid, especially when the core idea of the method, which happens to be what people have been trying to tell you is wrong, is completely overlooked.
A ÷ BC
A
= -C
B
No.
If it were
A ÷ B * C
I might agree.
A/ BC
=
A
--- * C
B
or
1
--- * A * C
B
The B and C are associated with each other. It's like having brackets. Yes its the same as B * C but it is implied that it has already occurred.
Well then, if you admit that the (9+3) must be multiplied by the coefficient, which is 2, then you also admit that the answer is 2, correct? If the answer was 288 then the coefficient would have to be (48 ÷ 2), rather than the 48 ÷ 2.JoshGod said:
Distributive law of multiplication states that BC cannot be separated on either side of the division sign. Thomas, you are saying that A/BC is the same as AC/B. And that is like saying A/B x C is the same as A/B x 1/C. Because by moving C from the bottom to the top, you are multiplying A/B by C's reciprocal and saying it equals the same. C does not equal 1/C, therefore A/B x C doesn't equal A/B x 1/C. And if you read left to right, like you are, that is what you are arguing forThomas Rembrandt said:IT IS THE SAME! What do you think BC means for gods sake. It means B*C. Where did you hear otherwise??ACman said:So you're trying to tell me thatCerdog said:Some people's understanding of BIDMAS is shocking. When you take care of brackets, you do everything INSIDE the brackets. You don't expand them, you don't distribute them, you just do everything inside them. So you get:
48÷2(9+3) = 48÷2(12)
2(12) is EXACTLY THE SAME as 2x12. The brackets, at this point, are irrelevant. For people trying to subsitute x = 12 here, it doesn't work, as implied multiplication is a) ambiguous and b) works differently for variables.
No. You are completely missing the point of what everyone is saying. Even if you ignore the different rules for variables and constants, your maths is incorrect. Let's look at the first line:DaMullet said:Actually, I want to double check my work.
48/2(9+x)=2
48/(18+2x)=2
48=2(18+2x)
48=36+4x
48-36=4x
4x=12
x=3
Yup, still works.
/thread
48/2(9+x)=2
What you have done is distributed the 2 into the brackets. THIS IS INCORRECT. As this is multiplication, and not "part of the brackets", you have to do division and multiplication from left to right, as they have equal precedence. So rather than:
48/(18+2x)=2
you should have:
24(9+x)=2
216+24x = 2
24x = -214
x = -8.917
Which is not 3, obviously.
Despite your algebraic method, you are still falling for the trap that so many others are falling for, which is to assume that the 2 is part of the brackets, which is WRONG. Algebra does not make your answer more valid, especially when the core idea of the method, which happens to be what people have been trying to tell you is wrong, is completely overlooked.
A ÷ BC
A
= -C
B
No.
If it were
A ÷ B * C
I might agree.
A/ BC
A
= --- * C
B
or
A * 1 * C
= ---
B
Here extension you talk about: 2(x+y) = 2x+2yInfiniteSingularity said:
But inside a formula you have to put brackets around the whole thing to be valid.
backwards this would be:
5/(2x +2y) can be written as 5/(2(x+y)). See the extra bracket? There is no magical bond between the bracket and its coefficient.