a data from gmat club

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a data from gmat club

by diebeatsthegmat » Mon Jul 11, 2011 6:56 pm
In the rectangular coordinate system, are the points (a,b) and (c,d) equidistant from the origin?

(1) a/b =c/d

(2) sq root a^2+sq root b^2=sq root c^2+sq root d^2
i know this data is discuss but i dont understand the answer is C
1 is clearly not sufficient becuase if a/b=c/d=1/1 the answer for the question in the text is no
but if a/b=c/d=1/2 or blah blah blah ( any number) the answer is yes
2 is not sufficient
1+2/ the question here is what will happen if a=b=c=d=1? the answer is still no
if a=-1b=1 c=1 d=-1 the answer is yes
i dont understand, can you guys please help me understand this

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by amit2k9 » Mon Jul 11, 2011 10:39 pm
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by diebeatsthegmat » Tue Jul 12, 2011 5:53 pm
yeah i know it discussed but i still dont understand

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by Frankenstein » Tue Jul 12, 2011 10:24 pm
Hi,
1 is clearly not sufficient becuase if a/b=c/d=1/1 the answer for the question in the text is no
You cannot say yes and no for certain in both the cases you mentioned
if a/b = c/d = 1
Consider (1,1) and (-1,-1). They are equidistant from origin. So, yes is also possible. You just can't say NO
but if a/b=c/d=1/2 or blah blah blah ( any number) the answer is yes
if a/b = c/d = 1/2
Consider (1,2) and (2,4). They are not equidistant from origin.
1+2/ the question here is what will happen if a=b=c=d=1? the answer is still no
Why is it NO? Both the points coincide. So they must be equidistant from origin.

Now, you can follow this:
https://www.beatthegmat.com/coordinate-t81057.html
This is another link. Not the link posted above. So, look into it.
Cheers!

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