Factoring Non-Monic Quadratic Trinomials

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So I was going through an exercise on non-monic quadratic trinomials and the question asked me to factorise 2x^2 - 10x - 28.

So my working out was:

2x^2 - 10x - 28

x^2 - 10x - 56

(2x - 14) (2x + 4) / 2

(x - 7) (2x + 4)

Howeve,r my final answer was not listed as the correct one in the answer section. The correct answer was in fact 2(x + 2)(x − 7). Which of the answers would be considered "fully factored". I would have though the form that involves only the terms within the brackets is preferential however, it appears I may be wrong.