BREAKING: Target Test Prep releases Brand New 2026 On Demand GMAT prep course

Redeem

DS ! i dont understand wat is it about

Expert replies
by vishubn » Fri Oct 03, 2008 5:46 am
If x(x - 5)(x + 2) = 0, is x negative?
(1) x2 – 7x ≠ 0
(2) x2 –2x –15 ≠ 0
A. Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient.
3
B. Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient.
C. BOTH statements TOGETHER are sufficient, but NEITHER statement ALONE is
sufficient.
D. EACH statement ALONE is sufficient.
E. Statements (1) and (2) TOGETHER are NOT sufficient.

vishu
Join the discussion
Source: — Problem Solving |

by shilpasetty » Fri Oct 03, 2008 6:19 am
If x(x - 5)(x + 2) = 0, is x negative?
(1) x2 – 7x ≠ 0
(2) x2 –2x –15 ≠ 0

1. x2 – 7x ≠ 0
can be factorised as x(x-7)≠0 i.e x≠0,7
This leaves us with 2 choices for x which is 5 and -2
So, not sufficent

2. x2 –2x –15 ≠ 0
can be factorised as (x+3)(x-5)≠0 i.e x≠-3,5
This leaves us again with 2 choices for x 0 and -2
Not sufficient.

Taking 1 and 2 together, x≠0,7,-3,5
So, it can be deduced that x= -2
Sufficient.
I think the ans is C. Correct me if I'm wrong.
Join the discussion

by stop@800 » Fri Oct 03, 2008 2:16 pm
Join the discussion