2✓450+6✓75-4✓128-7✓27
[tex]\it 2\sqrt{450} + 6\sqrt{75} - 4\sqrt{128} - 7\sqrt{27} = 2\sqrt{9\cdot25\cdot2} +6\sqrt{25\cdot3} - \\ \\ -4\sqrt{64\cdot2}-7\sqrt{9\cdot3}=2\cdot3\cdot5\sqrt2+6\cdot5\sqrt3-4\cdot8\sqrt2-7\cdot3\sqrt3= \\ \\ =30\sqrt2-32\sqrt2+30\sqrt3-21\sqrt3=-2\sqrt2+9\sqrt3=9\sqrt3-2\sqrt2[/tex]
