Advanced Math practice question

Answer: A. x + 2

Factor the numerator as a difference of squares: x² − 4 = (x − 2)(x + 2). The factor (x − 2) cancels with the denominator (allowed because x ≠ 2), leaving x + 2.

Why the other answers are wrong

B. x − 2

After cancelling (x − 2) from top and bottom, what's left in the numerator is the OTHER factor, (x + 2), not another (x − 2).

C. x² − 2

You cancelled an x from x² and left the −4 as −2 by halving it. Cancellation works on whole factors, not on individual terms — factor first.

D. x + 4

There's no route to x + 4. The numerator factors as (x − 2)(x + 2), and only the (x + 2) survives.

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