Is |x| = y - z? 1) x + y = z 2) x 0 Not very good with

Question

Is |x| = y - z? 

1) x + y = z 
2) x > 0 

Not very good with ABS Value. Can someone explain this in detail

BG · Answer

think it should be B)
If X>0 then mod X=X if X<0 then mod X= -X

coolfish1103 · Answer

Is |x| = y - z?

-> |x| = y - z & |-x| = y - z both fulfills

(1) x + y = z

-> |x| = y - z & |-x| = y - z

|x| = y - z & |-x| = y - z
x = y - z & -x = y - z
x - y = z & x + y = z

Insufficient:
If x is a positive value, it will not fulfill the condition.
- Original: |5| = 3 - 2  
- Condition (1): 5 - 3 = 2
If x is a negative value, it will not fulfill the condition.
- Original: |-5| = 3 - (-2)  
- Condition (1): -5 + 3 = -2

(2) x > 0

Insufficient, we do not know value of y and z in relation to x.

(1) & (2)
If x is positive from (2), applying (1) into the condition still will not fulfill the condition.

(E)

ps_dahiya · Answer

I think its C

What to find |x| = y-z ?

St1:
-x = y-z

1. y = 10, z = 5 , y-z = 5 Then x = -5 and main stem = TRUE
2. y = 5 , z = 10 , y-z = -5 Then x = 5 and main stem = FALSE
3. y = -5 , z = -10, y-z = 5 Then x = -5 and main stem = TRUE
4. y = -10, z = -5 , y-z = -5 Then x = 5 and main stem = FALSE

So INSUFF

St2:
x>0. No information about y and z. So INSUFF

Combined:
Taking the values taken in st1, only case 2 and 4 satisfies both statement 1 and 2. So main stem result is FALSE. So SUFF.

Guys, please correct me if I am wrong.

giddi77 · Answer

I also think it is C.

Is |x| = y-z ?
If the question is rephrased:

For x>0, Is x = y-z ? --- (I)
For x<0, Is x = -(y-z)? ---(II)

(1) x+y = z
This satisfies (II) which is true when x<0 ; but we don't know what happens when x>0. INSUFF.
(2) x>0. INSUFF because we don't know y & z.

Combining (1) & (2), we know that x can be only +ve number, so we need to answer the question (I) only!!
which is Is x = y-z? Given that x+y = z
Answer is NO.

Hence C.

lhotseface · Answer

I got C. Not 100% sure...

|x| = y -z.
If x> 0, x = y - z.
if x < 0. -x = y - z, x = -(y-z) = z -y => x+y = z.

II. INSUFF.
I. Gives that x+y=z., which would make the question stem true if x <0. We don't know that.

I+II -> Gives x > 0, then |x| = y -z must be equal to x = y-z., but II gives x+y =z, so we can anwer NO to the question stem.

jinesh

Is |x| = y - z?

1) x + y = z
2) x > 0

Not very good with ABS Value. Can someone explain this in detail

believe2 · Answer

agree with C.
...same reason as above.

andy_gr8 · Answer

I would go with C
Let see

Question stem gives (+/-)x=y-z
=> either (If x +ve)x=y-z or x=z-y(If x -ve)

a) x+y=z
When x is +ve this eq gives us 2y-z=z=>2y=2z=>y=z
Whn x=-ve we get z=z after replacing..So stmnt INSUFFICIENT

b)x>0 means x=y-z .But this is waht we have to prove
INSUFFICEINT
Combine and we get 
with x= z-y => which happens only when x is negative
So C

Is |x| = y - z? 1) x + y = z 2) x > 0 Not very good with

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