What is the value of │x + 7│?
(1) │x + 3│= 14
(2) (x + 2)^2 = 169
OA is given D. I think it should be C.
Please explain. Thanks!
Set 6 Q7 - DS
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I think the answer D is correct.
For first condition to be independently sufficient:
|x+7|
=|x+3|+|4|
But according to (1), |x+3| = 14;
Therefore,
|x+7|=14 +4
= 18
For second condition to be independently sufficient:
According to (2),
(x+2) = 13
i.e x= 11
Therefore,
|x+7| = |11+7| = 18
Thus, the answer is D.
For first condition to be independently sufficient:
|x+7|
=|x+3|+|4|
But according to (1), |x+3| = 14;
Therefore,
|x+7|=14 +4
= 18
For second condition to be independently sufficient:
According to (2),
(x+2) = 13
i.e x= 11
Therefore,
|x+7| = |11+7| = 18
Thus, the answer is D.
athakkar,
This is how i think it works:
(1) │x + 3│= 14
So, x+3=14 OR x+3=-14
>x=11 OR x=-17
Hence, two values for x from stmt.1 > insuff.
(2) (x + 2)^2 = 169
>(x+2)^2=13^2
>x+2=+-13
>x=11 OR x=-15
Hence, two values for x from stmt.2 > insuff.
But if we combine stmt1 and stmt2, we get x=11.
So the answer is C.
Just two things to be kept in mind here, the treatment for lMODl in stmt.1 and that stmt.2 has a square power, so there will be two solutions - negative and positive.
Hope this clarifies!
This is how i think it works:
(1) │x + 3│= 14
So, x+3=14 OR x+3=-14
>x=11 OR x=-17
Hence, two values for x from stmt.1 > insuff.
(2) (x + 2)^2 = 169
>(x+2)^2=13^2
>x+2=+-13
>x=11 OR x=-15
Hence, two values for x from stmt.2 > insuff.
But if we combine stmt1 and stmt2, we get x=11.
So the answer is C.
Just two things to be kept in mind here, the treatment for lMODl in stmt.1 and that stmt.2 has a square power, so there will be two solutions - negative and positive.
Hope this clarifies!