Mathematically - it does not matter. Both are correct.When making x the subject of this simple formula:
y = x + 2
Why does it become x = y - 2 instead of x = -2 + y ?
Basically; how do you know which order to arrange the terms? In this example; why does the -2 go after the y and not before?
To add another opinion (though we all agree that both are "correct"):When making x the subject of this simple formula:
y = x + 2
Why does it become x = y - 2 instead of x = -2 + y ?
Basically; how do you know which order to arrange the terms? In this example; why does the -2 go after the y and not before?
No, no , no!!!! I think that a student should develop their own style. Teachers should not push their styles down the student's throat.Just a hint--regardless of all these opinions, it may be wise to find out which method your teacher likes, and to use that format.
This student who made the post is in Algebra, possibly in a college setting. I feel that it is not incorrect to let this student know that they can use their own method. This may actually be a new concept to the student. Letting them know that they can have this freedom can even give them more confidence in math.
When making x the subject of this simple formula:
y = x + 2
Why does it become x = y - 2 instead of x = -2 + y ?
Basically; how do you know which order to arrange the terms? In this example; why does the -2 go after the y and not before?
Dr. P said it much better than I could have--and he knew what I wanted to say.My comment was not about methods, but about style: forms in which answers are to be given. You're arguing against something I didn't say.
I absolutely agree that multiple methods are good, and student-discovered methods can be even better. I am upset when teachers mark students wrong for using a different method than they were taught. But that is not what we are talking about in this thread:
As we've all said, it doesn't matter at all. All I said was that if a teacher has said to write all answers in descending order, then to do otherwise would be not to follow the instructions, just as if a problem said to write an answer without negative exponents. (I would still hope the teacher would make it clear that this is not a prohibition on ever writing anything in other orders, or ever using negative exponents.) And in fact, such an instruction would help make students aware that they can change the order, from whatever they come up with to the desired form.