Expand (x + 3) squared.
Answer and explanation
Correct answer: C. x squared + 6x + 9, with a middle term of twice 3x
- Step 1: Write (x + 3)(x + 3) and multiply each term. Step 2. x squared + 3x + 3x + 9. Answer: x squared + 6x + 9. Why not the others: x squared + 9 omits the cross terms; x squared + 3x + 9 includes only one 3x; x squared + 6x + 6 has the wrong constant.
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