test number 4 section 4 question number 25 indicates
Choice B is correct.
they the college board explains:
In f(x), factoring out the greatest common factor, 2x, yields
f(x) = 2x (x2 + 3x + 2).

however I do not find 2x to be a factor of X^3 +6X +4 because the 4 has no X associated with it. I did not get the answer as b either but c. Could you explain?

Thx John

I’ve got a full explanation of that question here (you can see all the official test questions I’ve explained here).

I think the problem you’re having is related to the initial factoring. You’re originally told that f(x)=2x^3+6x^2+4x. To factor a 2x out of that, you need to pull it out of each term (i.e, out of each part of the expression separated by a plus or minus sign). Here’s what your work might look like:

    \begin{align*}f(x)&=2x^3+6x^2+4x\\f(x)&=2x\left(\dfrac{2x^3}{2x}+\dfrac{6x^2}{2x}+\dfrac{4x}{2x}\right)\\f(x)&=2x(x^2+3x+2)\end{align*}

Does that help?

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