1. ## Assorted algebraic questions ( Read this before asking some questions! )

Im trying to lessen the stress put on people that answer maths qustions when the answers are in a previous post. So the big prob is when I was discussing algebra with a friend. I had arranged a simple question for him.
x+y=??? ( x and y are the variables. )
He had answered 2. I gave a brief explanation that a definite solution to the problem is impossible, unless the actual value of x and y is found.
He then said that if no definite answer is found, then the number 1 is used to substitute BOTH the variables in the equation.
Feeling disraught, I concluded the conversation and thought about what my friend had said. If 1 the value for x and y, then wouldnt the symbol representing one be the same? and is the thing about when a variable is unknwon, 1 is used to substitute? Help!! ( Oh yes, please forgive my poor grammare. I came from china) Should a year 8 student know all this stuff already? i am in year 8, and the top class i am in also. thank you for reading through all this clutter, i hope you will answer my questins.

You asked him a silly question, so he gave you a silly answer.

But if he was serious, then you two are in serious trouble with Math.

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x+y = ???

That is all the information?

8th Grade or not, that cannot have a unique (only one) answer.

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No. If a variable is unknown, 1 cannot be substituted for the variable just like that. For that matter, any number cannot be substituted for the variable just like that.
You have to have a reason to substitute any number to a variable.

Could it be that your question to your friend is not complete yet? Could it be that there is additional information that would say or imply that certain numbers could be substituted for x and y?

3. Originally Posted by ticbol
You asked him a silly question, so he gave you a silly answer.

But if he was serious, then you two are in serious trouble with Math.

-------------
x+y = ???

That is all the information?

8th Grade or not, that cannot have a unique (only one) answer.

---------------
No. If a variable is unknown, 1 cannot be substituted for the variable just like that. For that matter, any number cannot be substituted for the variable just like that.
You have to have a reason to substitute any number to a variable.

Could it be that your question to your friend is not complete yet? Could it be that there is additional information that would say or imply that certain numbers could be substituted for x and y?

So the answer would not be found? would I have simply answered x+y if somebody asked the same question?? The question 'exactly' the way i said it follows.
" me:hey tony i wanna see if you learnt your algebra well. will you allow me to test you?"
" tony:yeh"
" mekay, what is the answer to x+y"
" tony:2"
" me: sorry, it is wrong, it cannot be solved, as the unkwons are not known"
" tony:well my dad said that when you dont know the unknwown you use one insted"
" me: i think your dad is wrong tony, sorry if i offended you"
"tony: go away!"

4. If x+y= ??? then the answer is undefined. You can't calculate the answer if you dont know variables x and y value.