GMAT: Data Sufficiency 6

[ajone86]

Problem number 28....

In the first one, what if x =1, then it would prove it to be 1/2 or .5, which is not an integer????

[vanidharatreya]

prob 28, was wondering if x was odd ?

[shakthiyj]

dese r answers for which questions?

[sallo808]

Sal: Thanks for these great videos.

For problem 29

(x+1)2=X2

Cant we not remove the "2"square from both side?

X+1=X

1=X-X

1=0

That doesnt give us value of X. How would we know in exam what to choose?

Thanks

[shell3202]

That would be taking the square root of both sides, but in order to do that you will have 2 roots: the positive and the negative. So you'll have to account for each case:

x+1 = x or x+1 = -x

The first case ends up being discarded and the 2nd case is 2x+1 = 0. As Sal explained, it's easy to forget this and get the question wrong, you're better off expanding the squared term and solving that way.

[ikipi1]

very useful info  thx

[sadscene1]

u r great mr salman your videos are really helpful for me and just to comment u i made my youtube account

[kadsawy]

great!