Is |x| = y - z ?
(1) x + y = z
(2) x < 0
here is how how approached :-
To prove:- x=y-z
OR -x=y-z or x=z-y
a) x+y=z
or x=z-y {sufficient}
b) x<0 {insufficient}
Plz. let me know if I am wrong somewhere.....
Another Absolute value question
This topic has expert replies
the answer is C since:
(1) x+y=z --> -x=y-z thus |x|=y-z is true only if x<=0.
for example, if x=1 then according to (1): -1=y-z which contradicts: 1=y-z
insufficient.
(2) x<0 insufficient as you said.
(1+2) sufficient. x<0, therefore in statement (1): -x=y-z, x is positive, which leads us to conclude that |x|=y-z is true.
(1) x+y=z --> -x=y-z thus |x|=y-z is true only if x<=0.
for example, if x=1 then according to (1): -1=y-z which contradicts: 1=y-z
insufficient.
(2) x<0 insufficient as you said.
(1+2) sufficient. x<0, therefore in statement (1): -x=y-z, x is positive, which leads us to conclude that |x|=y-z is true.
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Thanks......rtfact wrote:the answer is C since:
(1) x+y=z --> -x=y-z thus |x|=y-z is true only if x<=0.
for example, if x=1 then according to (1): -1=y-z which contradicts: 1=y-z
insufficient.
(2) x<0 insufficient as you said.
(1+2) sufficient. x<0, therefore in statement (1): -x=y-z, x is positive, which leads us to conclude that |x|=y-z is true.
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i have same ques.
If in any ques it is asked mod x = mod y
and nothing about -ve and +ve.
Do we need to prove , x=y AND -x =-y........
I am putting essence on AND...it will be AND (both condition)or OR...means any1 of condition
If in any ques it is asked mod x = mod y
and nothing about -ve and +ve.
Do we need to prove , x=y AND -x =-y........
I am putting essence on AND...it will be AND (both condition)or OR...means any1 of condition
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vivek.kapoor83,
there can be different cases for |x| =|y|
x + -
y + -
check how many combos you can have.
there can be different cases for |x| =|y|
x + -
y + -
check how many combos you can have.
Cubicle Bound Misfit
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Is |x|=y-z
statement 1:
x+y=z
x=z-y( if x>0)
x=y-z( if x<0)
Insufficient
statement 2
x<0
Insufficient
Combining both the statements we have x=y-z for x<0
So the ans should be C..Let me know if you still have any doubts
statement 1:
x+y=z
x=z-y( if x>0)
x=y-z( if x<0)
Insufficient
statement 2
x<0
Insufficient
Combining both the statements we have x=y-z for x<0
So the ans should be C..Let me know if you still have any doubts