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If x^2 + 4x + 3 is odd, then which one of the following cou
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18 Apr 2018, 12:00
18 Apr 2018, 12:00
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80% (00:53) correct
19% (00:53) wrong based on 52 sessions
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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
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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
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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?
