I am not sure how I mixed that up but for some reason in my head I was thinking “Do Addition then (should read “and”) Subtraction in order from left to right”. This is why it is a shower thought and why I am brushing up on my math. haha
This is the back story of the silliness from another comment. I simply misremembered what to do and did addition before subtraction instead of left to right. I am still not sure exactly why because I literally just read a section on order of operations and my brain did the rest. I am usually not so bad at math, but my brain can be my worst enemy. haha
did addition before subtraction instead of left to right
No, what you actually did was put it inside brackets, thus changing the number of terms. Doing addition first gives the exact same answer as doing subtraction first…
subtraction first 10-1+1=9+1=10
addition first 10+1-1=11-1=10
You did 10-(1+1), hence the wrong answer. It doesn’t matter which order you do it, though often students make mistakes with signs when they change the order, which is why we teach to do left to right.
The brackets are used to make the equation look cleaner, and the issue for declaring the statement true was doing Addition and Subtraction in the wrong order.
A - ( B x C ) + ( D x E ) = A - ( B x C ) - ( D x E )
10 - 1 - 1 = 8 regardless of order because it is all subtraction.
edit: Brain still waking up it is not the same regardless of order, but you do it left to right making it incorrect to do 1-1 first.
By doing it out of order and incorrectly I was able to make my statement true that as long as A was greater than the sum of B-E both sides would be equal.
The brackets are used to make the equation look cleaner
No, they’re used to show deviations from the usual order of operations. If I want 2+3x4 to equal 20, then I have to write (2+3)x4.
10 - 1 + 1 = 8 doing the addition first
No it isn’t. 10+1-1=11-1=10 is doing the addition first. Note same answer. You in fact did 10-(1+1) - you added brackets which changed the answer, thus a wrong answer
10 - 1 - 1 = 8 regardless of order because it is all subtraction
Not all of it. You’re forgetting the 10 is really +10. -10-1-1 would be all subtraction. +10-1-1 is addition and subtraction.
it is not the same regardless of order
Yes it is! 😂 It is always the same regardless of order, as I have just shown you, again.
10-1+1=9+1=10
10+1-1=11-1=10
-1+1+10=0+10=10
1-1+10=0+10=10
1+10-1=11-1=10
-1+10+1=9+1=10
you do it left to right making it incorrect to do 1-1 first.
It’s NOT incorrect to do 10-1+1 or 10+1-1. It IS incorrect to do 10-(1+1), which is what you did
By doing it out of order and incorrectly I was able to make my statement true
It was solely because you did it incorrectly. Order doesn’t change anything.
I am not going to argue with you about it. This was resolved almost a month ago.
Read the original equation again, plug some numbers into it, and try again. If that doesn’t help, read the rest of the thread. If you still don’t get it I cannot help you.
This is the back story of the silliness from another comment. I simply misremembered what to do and did addition before subtraction instead of left to right. I am still not sure exactly why because I literally just read a section on order of operations and my brain did the rest. I am usually not so bad at math, but my brain can be my worst enemy. haha
No, what you actually did was put it inside brackets, thus changing the number of terms. Doing addition first gives the exact same answer as doing subtraction first…
subtraction first 10-1+1=9+1=10
addition first 10+1-1=11-1=10
You did 10-(1+1), hence the wrong answer. It doesn’t matter which order you do it, though often students make mistakes with signs when they change the order, which is why we teach to do left to right.
The brackets are used to make the equation look cleaner, and the issue for declaring the statement true was doing Addition and Subtraction in the wrong order.
A - ( B x C ) + ( D x E ) = A - ( B x C ) - ( D x E )
Using your example:
10 - 1 + 1 = 10 doing the subtraction first. 10 - 1 + 1 = 8 doing the addition first.
When doing the other side of the equation:
10 - 1 - 1 = 8 regardless of order because it is all subtraction. edit: Brain still waking up it is not the same regardless of order, but you do it left to right making it incorrect to do 1-1 first.
By doing it out of order and incorrectly I was able to make my statement true that as long as A was greater than the sum of B-E both sides would be equal.
No, they’re used to show deviations from the usual order of operations. If I want 2+3x4 to equal 20, then I have to write (2+3)x4.
No it isn’t. 10+1-1=11-1=10 is doing the addition first. Note same answer. You in fact did 10-(1+1) - you added brackets which changed the answer, thus a wrong answer
Not all of it. You’re forgetting the 10 is really +10. -10-1-1 would be all subtraction. +10-1-1 is addition and subtraction.
Yes it is! 😂 It is always the same regardless of order, as I have just shown you, again.
10-1+1=9+1=10
10+1-1=11-1=10
-1+1+10=0+10=10
1-1+10=0+10=10
1+10-1=11-1=10
-1+10+1=9+1=10
It’s NOT incorrect to do 10-1+1 or 10+1-1. It IS incorrect to do 10-(1+1), which is what you did
It was solely because you did it incorrectly. Order doesn’t change anything.
I am not going to argue with you about it. This was resolved almost a month ago.
Read the original equation again, plug some numbers into it, and try again. If that doesn’t help, read the rest of the thread. If you still don’t get it I cannot help you.
Nor should you. I’m a Maths teacher.
And yet you still don’t understand what’s wrong with what you said.
That’s what you need to do. You’re the one coming up with wrong answers when you change the order. Changing the order doesn’t change the answer.
It’s not me who doesn’t get it. I teach it.
I feel bad for your students if you cannot see why you are wrong here.
My students know I’m right. Everyone’s students know that’s right. It’s only adults who’ve forgotten the rules who get this wrong.
Whatever you say. Enjoy the egg on your face bud.
Ah. So you gave addition a higher precedence than subtraction. That makes sense.