Another thick maths query...

[charliecat]

\link{http://www.mathsisfun.com/algebra/add-subtract-balance.html\dd whos 8 has some homework like this}
She didnt have a clue...I worked it out, told her how to do it, practised, she got it in the end...
The last question however was....

14 + X = 25 + X write down some more

ways this could be shown.....
WHAT???
Couldnt work it out and had to leve it...completed the sum...but couldnt work out how else to show it.

Oh lord!! I have just sat my maths exam and i have no idea am very very

Hey? If X is the same number how can it produce the same when added to 14 or to 25??? What am I missing? (Is now a good time to admit I have maths A level?!)

It wasnt X ...it was a blank box....I put 11 in the first one, 0 in the 2nd... to balance it out, scale like....

I would think you have to make two separate sums which both lead to the same answer.

eg

14 + 16 = 25 + 5
(so 14 + 16 = 30, and so does 25 + 5)

Hmmm - I'm not sure. I can't make it make sense.
14+x = 25+x

+x-x = 25-14 (get all like terms on same side)

0 = 11 (!!! not possible !!!)

Reckon I'm missing something here.

You could also put 12 in the first box, 1 in the second.

13 in the first box, 2 in the second etc

Oh right..get it now.

So -
14+12 = 25+1
14+13 = 25+2 and so on.

WWB put it a bit better .

I think charliecat and WWB have the right idea, but I don't think much of the way the question is styled. Later on, x will indicate one number so it is not very clever letting children think x can be 2 different numbers in one equation.

Oh you confused me by using X twice which would mean they were the same number iyswim. If it was 14 + x = 25 + y it would have made perfect sense!

ahh so we could have gone on forever suggesting scenarios? (sp)

Agree GDG. So x wasn't actually used twice in each equation? That was just how cahrliecat showed it here? OK I take my comment back.

The question is fick. In algebra, when you use "X" in the same equation, they refer to the same number. It should have been "X" and "Y" instead.

IT WAS BLANK BOXES >>>>SORRY!!!

charliecat .

14 + [ ] = 25 + [ ]
Substitute X and Y into the boxes
14 + X = 25 + Y
X = 25 + Y - 14
X = 11 + Y

Therefore, if:
Y = 1, X = 12
Y = 2, X = 13
Y = 3, X = 14 etc

ill try that on paper when those numbers stop jumping round in fron of my eyes LOL