ACT Math · Polynomial and rational functions
Which expression is equivalent to (x²-4)/(x²+5x+6) for x ≠ -2, -3?
Which expression is equivalent to for ?
Answer and explanation
Answer: F: x-2/x+3
Factor both parts: and . Cancel the common factor , which is allowed since : , choice F. Check with : the original is and . Choice G () cancels the wrong factor. Choice H () changes a sign in the denominator. Choice J () cancels the entire denominator as if it were one factor. Only common factors, never common terms, can be cancelled. The restrictions stay in force after cancelling.
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