5.
[tex]a) \ \sqrt{3^{2}+4^{2}}= \sqrt{9+16} = \sqrt{25} = 5\\\\b) \ \sqrt{9\sqrt{16}} = \sqrt{9\cdot4} = \sqrt{36} = 6\\\\c) \ \sqrt{16} + \sqrt{36} = 4 + 6 = 10\\\\d) \ \sqrt{\frac{98}{128}} = \sqrt{\frac{98:2}{128:2}} = \sqrt{\frac{49}{64}} = \frac{\sqrt{49}}{\sqrt{64}} = \frac{7}{8}[/tex]
