Factorise 2x squared - 8 completely.
Answer and explanation
Correct answer: D. 2(x - 2)(x + 2)
- Step 1: Take out the common factor 2: 2(x squared - 4). Step 2. Factorise the difference of two squares: 2(x - 2)(x + 2). Answer: 2(x - 2)(x + 2). Why not the others: 2(x - 4)(x + 4) expands to 2x squared - 32, (x - 2)(x + 2) leaves out the common factor 2, and 2(x - 2) squared expands to 2x squared - 8x + 8.
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