9.
a)
[tex]3\sqrt{5} = \sqrt{3^{2}\cdot5} =\sqrt{9\cdot5} = \sqrt{45}\\\\0,5\sqrt{3} = \sqrt{0,5^{2}\cdot3} = \sqrt{0,25\cdot3} =\sqrt{0,75}[/tex]
b)
[tex]\sqrt{700} =\sqrt{100\cdot7} = \sqrt{10^{2}\cdot7} = 10\sqrt{7}\\\\\sqrt{48} = \sqrt{16\cdot3} = \sqrt{4^{2}\cdot3} =4\sqrt{3}[/tex]
10.
[tex]2\sqrt{49}-6\sqrt{7}+3\sqrt{7}-\sqrt{28}=2\sqrt{7^{2}}-3\sqrt{7}-\sqrt{4\cdot7} = 2\cdot7 - 3\sqrt{7}-\sqrt{4}\cdot\sqrt{7}=\\\\=14-3\sqrt{7}-2\sqrt{7} = 14-5\sqrt{7}[/tex]
