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What is the value of k? where k is an integer.

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Source: — Data Sufficiency |

by DavidG@VeritasPrep » Sun Sep 10, 2017 3:47 pm
Vincen wrote:What is the value of integer k?

(1) k + 3 > 0
(2) k^4 ≤ 0

OA is B.

How can I determine the value of k? Please help.
Statement 1 you can toss pretty quickly. k > -3, so k could be -2 or -1, etc.

The key to statement 2 is recognizing that if you take a base and raise it to an EVEN exponent, the value can never be negative. So if k^4 is less than or equal to 0, and it can't be less than 0, then it has to be equal to 0. Thus k = 0. Statement 2 alone is sufficient. The answer is B
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by Jay@ManhattanReview » Sun Sep 10, 2017 11:05 pm
Vincen wrote:What is the value of integer k?

(1) k + 3 > 0
(2) k^4 ≤ 0

OA is B.

How can I determine the value of k? Please help.
Statement 1: k + 3 > 0

=> k > -3

No unique value of k. Insufficient.

Statement 2: k^4 ≤ 0

We see that k has an exponent of an even number, thus k^4 must be non-negative.

Since k^4 ≤ 0, the only possible non-negative value is 0. Sufficient.

The correct answer: B

Hope this helps!

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