Which of the following is equivalent to
$$\frac{\left(2x+4\right)}{2x^2+8x+8}$$
For all values of x for which both expressions are defined?
$$A.\ \frac{1}{2x^2+6}$$
$$B.\ \frac{1}{9x+2}$$
$$C.\ \frac{2}{x+6}$$
$$D.\ \frac{1}{x+4}$$
$$E.\ \frac{1}{x+2}$$
The OA is E.
I think that it is a simple question, I just need to re-write the expression, then
$$\frac{2\left(x+2\right)}{2\left(x^2+4x+4\right)}=\frac{2\left(x+2\right)}{2\left(x+2\right)^2}=\frac{1}{\left(x+2\right)}$$
And that's all, right? Is there a strategic approach to this PS question? Can any experts help, please? Thanks!
Which of the following is equivalent to...
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- ErikaPrepScholar
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Your approach is the best way to solve the problem. Algebraic manipulation is a common strategy on GMAT problems.
Like you mentioned, this is a relatively simple problem. If a student wasn't sure how to simplify the equation, this problem could also be solved by strategically testing numbers in each equation, but this would be much less efficient.
Like you mentioned, this is a relatively simple problem. If a student wasn't sure how to simplify the equation, this problem could also be solved by strategically testing numbers in each equation, but this would be much less efficient.
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- Jeff@TargetTestPrep
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After factoring the denominator, we can simplify the given expression:AAPL wrote:Which of the following is equivalent to
$$\frac{\left(2x+4\right)}{2x^2+8x+8}$$
For all values of x for which both expressions are defined?
$$A.\ \frac{1}{2x^2+6}$$
$$B.\ \frac{1}{9x+2}$$
$$C.\ \frac{2}{x+6}$$
$$D.\ \frac{1}{x+4}$$
$$E.\ \frac{1}{x+2}$$
(2x + 4)/(2x + 4)(x + 2) = 1/(x + 2)
Answer: E
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