Thank you for using the timer - this advanced tool can estimate your performance and suggest more practice questions. We have subscribed you to Daily Prep Questions via email.

Customized for You

we will pick new questions that match your level based on your Timer History

Track Your Progress

every week, we’ll send you an estimated GMAT score based on your performance

Practice Pays

we will pick new questions that match your level based on your Timer History

Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.

Thank you for using the timer!
We noticed you are actually not timing your practice. Click the START button first next time you use the timer.
There are many benefits to timing your practice, including:

The way I understand it, you cannot conclude that (a+b)^2/(a+b)^2 = 1 because a, b, and c are not defined as positive integers. Therefore, if a = -b, then (a+b)^2 would = 0 and the equation would be undefined.

2) b/c = [(a+b)^2 / (a^2 + 2ab + b^2)] - 1----- If this is given to be true then does not this imply that (a^2 + 2ab + b^2) =/= 0 i.e. a is never equal to -b.

has to be ! otherwise the expression is undefined !!

a <> 0

Bluebird's solution assumes an undefined expression (i.e a+b=0). This is not the official GMAT approach ! the official GMAT will not assume undefined solutions. So I second (B).

has anyone heard of the actual gmat throwing these kinds of problems at people?

cus thats a tough one...im thinking that if i got this problem on the gmat and noticed that a could equal b, i might still choose B because i'd be like.."naww they wouldn't do this on the real thing"

then id get it wrong even when i knew the concept they were testing..

Thanks guys. Yes thats exactly where I saw it. I just couldn't agree with the answer at that time. But now its clearer. If I see this kind of problem in real GMAT I will be pretty happy, since it would imply that I am doing pretty well so far

I can put it in this way,
b/c = (a+b)^2/(a+b)^2 - 1
hence a and b is not defined as +ve or -ve, but still we'll always get square term as +ve, if it's not integer, then also we can make it 0, becoz, 2/3*3/2 is always 1.
Hence b/c = 1-1 = 0, so B=0.
Hence B should be the soluition.