Ответ:

[tex](4\sqrt{3} +\sqrt{27} )*\sqrt{3} =21[/tex]

[tex]1)4\sqrt{3} +\sqrt{27} =4\sqrt{3} +\sqrt{9*3} =4\sqrt{3}+3\sqrt{3} =7\sqrt{3}[/tex]

[tex]2)7\sqrt{3} *\sqrt{3} =7*3=21[/tex]