Is |x| = y – z?

[sanju09]

Is |x| = y - z?
(1) x + y = z.
(2) x < 0.

[sam2304]

1. x + y = z
x = z - y
-x = y - z
So |x| = y - z. SUFFICIENT

2. x < 0 -> no info about y and z. INSUFFICIENT.

IMO A.

[killer1387]

Is |x| = y - z?
(1) x + y = z.
(2) x < 0.

C IMO

[sanju09]

(1) If x + y = z, then x = z - y and hence |x| = z - y if x > 0, OR |x| = y - z if x < 0. Insufficient

(2) If x < 0 then |x| > 0, but if it is equal to y - z or not, we never know. Insufficient

Taking (1) and (2) together, we can find that x = z - y and x < 0, and hence

[spoiler]YES to |x| = y - z.

Sufficient

Take C

@killer1387, please care giving explanations to your brilliant answers.[/spoiler]