10

Set 3: Quadratic Equations (Advanced)

Explanation

Answer: A

Factor completely: 2x2+6x2x^2 + 6x

A.

2x(x+3)2x(x + 3)

✓ Correct
B.

x(2x+6)x(2x + 6)

C.

2(x2+3x)2(x^2 + 3x)

D.

2x(x3)2x(x - 3)

Detailed Explanation

Choice A is correct. Choice A is the correct answer. To factor completely, always look for a Greatest Common Factor (GCF) first. 1. The coefficients are 2 and 6. The GCF is 2. 2. The variables are x2x^2 and xx. The GCF is xx. 3. Combine them: The total GCF is 2x2x. 4. Divide each term by 2x2x: 2x2/2x=x2x^2/2 x = x and 6x/2x=36x/2 x = 3. So, the factored form is 2x(x+3)2x(x + 3). Choice B is incorrect because 2x+62x+6 can still be factored further (divisible by 2). Choice C is incorrect because it leaves an xx inside that could be factored out. Choice D is incorrect because expanding 2x(x3)2x(x-3) gives 2x26x2x^2 - 6 x, which has the wrong sign.

Key Steps:

The correct answer is 2x(x+3)2x(x + 3)

Why others are wrong:
B: Choice B is incorrect and may result from a calculation error.
C: Choice C is incorrect and may result from a calculation error.
D: Choice D is incorrect and may result from a calculation error.

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