GRE Prep Club Daily Prep
Thank you for using the timer - this advanced tool can estimate your performance and suggest more practice questions. We have subscribed you to Daily Prep Questions via email.
Customized
for You
Track
Your Progress
Practice
Pays
Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.
If x^2 + 4x + 3 is odd, then which one of the following cou
[#permalink]
18 Apr 2018, 12:00
18 Apr 2018, 12:00
Expert Reply
1
Bookmarks
00:00
Question Stats:
87% (00:53) correct
12% (00:32) wrong based on 47 sessions
Hide Show timer Statistics
If \(x ^2 + 4x + 3\) is odd, then which one of the following could be the value of x ?
(A) 3
(B) 5
(C) 9
(D) 13
(E) 16
(A) 3
(B) 5
(C) 9
(D) 13
(E) 16
If x^2 + 4x + 3 is odd, then which one of the following cou
[#permalink]
Updated on: 17 Nov 2021, 16:33
Updated on: 17 Nov 2021, 16:33
1
It is good to note that
Odd + Odd = Even
Even + Even = Even
Odd + Even = Odd
&
Odd * Odd = Odd
Even * Even = Even
Even * Odd = Even
Now coming to the question:
It states x^2 + 4x + 3 is ODD
We know that whatever be the value of x, 4x will always be even (Even * Odd (or Even) = Even)
We also know that 3 is Odd
Therfore we can rewrite the expression in the question: x^2 + 4x + 3 is Odd as
x^2 + Even + Odd is Odd
We know (Even + Odd) is Odd
Therefore,
x^2 + Odd is Odd
For the above to be true,
x^2 has to be even and this will happen only when x is EVEN.
The only even number in the answer choice is 16.
Correct Answer : Option E
Odd + Odd = Even
Even + Even = Even
Odd + Even = Odd
&
Odd * Odd = Odd
Even * Even = Even
Even * Odd = Even
Now coming to the question:
It states x^2 + 4x + 3 is ODD
We know that whatever be the value of x, 4x will always be even (Even * Odd (or Even) = Even)
We also know that 3 is Odd
Therfore we can rewrite the expression in the question: x^2 + 4x + 3 is Odd as
x^2 + Even + Odd is Odd
We know (Even + Odd) is Odd
Therefore,
x^2 + Odd is Odd
For the above to be true,
x^2 has to be even and this will happen only when x is EVEN.
The only even number in the answer choice is 16.
Correct Answer : Option E
Re: If x^2 + 4x + 3 is odd, then which one of the following cou
[#permalink]
19 Apr 2018, 03:21
19 Apr 2018, 03:21
On solving for z, one value we get for x is -3.
Square of x in that case would be 9. Can this not be the answer?
Square of x in that case would be 9. Can this not be the answer?
