Is x a positive integer? (1) x 0 (2) x^2 + 16 = 25

Question

Is x a positive integer?

(1) x > 0

(2) x^2 + 16 = 25

the original answer is C.

I'm confused why the answer is not A. I know that zero is define as neither negative or positive, but based on the inequality symbol, the zero (0) should not be included?

That's why I thought statement (1) alone is sufficient.

Please expert help.

Thanks in advance

KanishkM · Answer

Would like to pitch in,

(1) x>0 
If x> 0, this just tells about the sign of x, Now x can be a fraction, number or an integer, Example x can be
x=1, is an Integer(Answering the question as Yes)
x = 1.1, is not an Integer (Answering the question as No)

(2) x^2+16=25
x^2 = 9
will give 2 values, x can be 
3(Answering the question as Yes)
-3(Answering the question as No)

Now when you combine both the statements, you know that x>0 and from B, the only value which satisfies both the statements is 3.

Giving Answer as C

DisciplinedPrep · Answer

Statement 1 : x > 0
Statement 1 says that x is a positive number, but may or may not be an integer. Hence Statement 1 by itself is NOT Sufficient. 
 
Statement 2 : x^2 + 16 = 25
Solving for x, we get x^2 = 9, i.e. x = 3, or -3. Hence Statement 2 by itself is NOT Sufficient.

Combining Statement 1 & Statement 2 : x > 0 & x = +3, or -3. We get a unique value for x, i.e. x = 3. Hence Statement 1 and 2 together is Sufficient.

Therefore, the Correct Answer is Option C.

akurathi12 · Answer

Statement 1. x>0

Option 1. If 'x' is an integer statement sufficient
Option 2. If 'x' is a fractional number 1/2, 3/4... statement not sufficient

Statement 2. x^2+16=25 => x will have 2 values x=3 or x=-3 not sufficient

Statement 1&2 - From statement 1 x is positive, statement 2 x=3 Sufficient

Answer:-C

ocelot22 · Answer

(1) x >0 no integer restriction is given here so x can be ANYTHING >0 Let x =1 is x a positive integer? Yes
Let x =1.2 Is x a positive integer? No since we get a Yes and No, the statement is not sufficient

(2) x^2+16=25 subtract 16 from each side and we get x^2=9, and x = +3 or x=-3 NS

(1) and (2) x=-3 or x=+3 and x >0, then x must =+3 sufficient. Answer is C

aggvipul · Answer

St. 1 - X>0 is insufficient as X can be a decimal no.
St. 2 - x^2+16=25 is insufficient as X can be either +3 or -3

Combining st. 1 and st.2 renders only one possible value of X, which is +3 and hence this combination is sufficient. Answer C

Is x a positive integer? (1) x > 0 (2) x^2 + 16 = 25

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