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Can I cross off a variable as you crossed off "C" from numerator and denominator. What if value of C is 0.
If it is mentioned that C is not equal to zero, then I can cross off the C from both side or from numerator and denominator.
From above thought, I think option C is correct here.

Kinshook
Bunuel
If x ≠ –1, then \(\frac{2cx^2 + 4cx + cy}{c(x + 1 )^2} =\)

(1) y = 2
(2) c = 3


If x ≠ –1, then
\(\frac{2cx^2 + 4cx + cy}{c(x + 1 )^2} = \frac{2(x+1)^2 + (y-2)}{(x+1)^2} = 2 + \frac{(y-2)}{(x+1)^2}\)

(1) y = 2
\(\frac{2cx^2 + 4cx + cy}{c(x + 1 )^2}= 2 + \frac{(y-2)}{(x+1)^2} = 2\)
SUFFICIENT

(2) c = 3
Expression is not dependent on C
NOT SUFFICIENT

IMO A
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gvij2017
Can I cross off a variable as you crossed off "C" from numerator and denominator. What if value of C is 0.
If it is mentioned that C is not equal to zero, then I can cross off the C from both side or from numerator and denominator.
From above thought, I think option C is correct here.

Kinshook
Bunuel
If x ≠ –1, then \(\frac{2cx^2 + 4cx + cy}{c(x + 1 )^2} =\)

(1) y = 2
(2) c = 3


If x ≠ –1, then
\(\frac{2cx^2 + 4cx + cy}{c(x + 1 )^2} = \frac{2(x+1)^2 + (y-2)}{(x+1)^2} = 2 + \frac{(y-2)}{(x+1)^2}\)

(1) y = 2
\(\frac{2cx^2 + 4cx + cy}{c(x + 1 )^2}= 2 + \frac{(y-2)}{(x+1)^2} = 2\)
SUFFICIENT

(2) c = 3
Expression is not dependent on C
NOT SUFFICIENT

IMO A


Yes
I think you have a valid point.
Corrected.
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If x is not equal to -1 then (2cx^2+4cx+cy)/(c(x+1)^2) =?

1. y=2;
This reduces the expression to (2cx^2+4cx+2c)/(c(x+1)^2)
= (2c(x^2+2x+1))/(c(x+1)^2)
= (2c(x+1)^2)/(c(x+1)^2)
Since we know from the question that x is not equal to -1, the above expression results in a value of 2 for values of c not equal to 0. However when c=0, the expression is undefined. But there is no restriction on the value c such that c is not equal to 0, hence statement 1 is not sufficient on its own.

2. c=3 leads to
(6x^2+12x+3y)/(c(x+1)^2)
When y=2 and x=1, (6(1^2)+12(1)+3(2))/(3(2^2))
=(24)/(12)=2
When y=1 and x=1,
(6*1^2+12*1+3*1)/(3(2^2))
=21/12 =7/4 and this is different from the previous value of 2. Statement 2 is not sufficient.

Combining 1 and 2 yields (2*3(x+1)^2)/(3(x+1)^2) = 2 for all values of x not equal to-1. Hence 1+2 is sufficient.

Answer is therefore C.

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Firstly, I solved the problem and found A as an answer.
Then a reply made stated that c should not be zero for results to be valid.
Then I relooked my solution and confirmed that statement 2 provides that c is not zero and is essential to the solution.
I revised my solution and put C as an answer.
But now OA is A.

Please correct.

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