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Algebraic expression - D

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by agps » Sat Sep 01, 2007 11:01 am
this is a data sufficiency question right?

1) b-c=c-b -> 2b=2c -> b=c, then b-c=0, so it's sufficient.

2) b/c=c/b -> b^2=c^2, since both b and c > 0 this also means that b=c, also sufficient, answer D.
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Re: Algebraic expression - D

by jaspreet.sharma » Tue Sep 04, 2007 4:23 pm
tanyajoseph wrote:If a > 0, b>0, and c>0, is a(b-c) = 0?

1) b-c = c-b
2) b/c = c/b


Shouldnt the answer be A
Correct me if am wrong.

As 2nd cond says

b^2 = c^2
b^2 - c^2 =0
(b-c)(b+c)= 0

b=c or b=-c

and if b=-c then a(b-c) is not equal to 0
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Re: Algebraic expression - D

by blah45 » Tue Sep 04, 2007 4:43 pm
jaspreet.sharma wrote:
and if b=-c then a(b-c) is not equal to 0
b>0 and c > 0, so b=-c will NOT hold true.

Thus, my answer is D.
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Re: Algebraic expression - D

by jaspreet.sharma » Tue Sep 04, 2007 5:24 pm
blah45 wrote:
jaspreet.sharma wrote:
and if b=-c then a(b-c) is not equal to 0
b>0 and c > 0, so b=-c will NOT hold true.

Thus, my answer is D.

Oh thanks for correcting me :) ....i missed that part.....
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