Question

simplify

Answer 1

\[\sqrt{2x}(7+\sqrt{2x})\]

Answer 2

Please, there's no need to do this stuff repeatedly when Wolfram|Alpha does it perfectly, if all you need is to check your answer. Once you get one wrong then come here.

BTW, for this last one you got it wrong. The expression does not simplify beyond its two terms. You can only distribute the sqrt(2x), for which you get
7sqrt(2x)+2x

Answer 3

2x+7\[\sqrt{2x}\]