# quickie

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I was just wondering if this is correct: (21 x root2)xy - (20 x root2)xy = (root2)xy by root2 I mean the square root of 2.

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Yes, just take out the common factor. Let k = (root2)xy to give

21k - 20k = k.

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Yeah, I just worked it out, and was about to say... thanks anyway though ;-)

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Yes, correct, but only if by "20 x root2" you mean 20 * root2
(*)

Rearrange and you have:
(21-20)*root2*xy

If it's homework.... you're in big trouble. It must mean your math knowledge is _several_grades_ below your homework. edit:nevermind if you worked out but anyway, if you haven't worked out instantly...

****************
(*) i guess that's the problem....

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yeah by 'x' I meant '*'. I have no idea why I put x...
And I was only double checking, cause I've got a pretty heafty problem to solve and didn't want to go wrong near the beginning (although I did somewhere else.... :'()

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