Simplify (x^2 - 9) / (x + 3), for x not equal to -3.
Answer and explanation
Correct answer: B. x - 3
- Step 1: Factorise the difference of two squares: x^2 - 9 = (x - 3)(x + 3). Step 2. Cancel the common factor (x + 3) to leave x - 3. Answer: x - 3. Why not the others: x + 3 cancels the wrong factor, x^2 - 3 divides only the constant, and x - 9 cancels terms instead of factors.
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