Answer:
[tex]2(\sqrt[]{7}-2\sqrt[]{3})[/tex]Step-by-step explanation:
Since the radicals are different, the only thing to do is to write 4 as 2*2 and put 2 in evidence:
[tex]\begin{gathered} 2\sqrt[]{7}-4\sqrt[]{3} \\ =2\sqrt[]{7}-2\cdot2\sqrt[]{3} \\ =2(\sqrt[]{7}-2\sqrt[]{3)} \end{gathered}[/tex]