Answer:
The length of the missing side is
[tex]4 \sqrt{5} \\ if \: you \: want \: it \: not \: simplified \: it \: would \: be \: \\ \sqrt{80} [/tex]
Step-by-step explanation:
You could do Pythagorean theorem which is:
[tex] {a}^{2} + {b}^{2} = {c}^{2} \\ {8}^{2} + {4}^{2} = {c}^{2} \\{64} + {16} = {c}^{2} \\ \sqrt{80} = {c}^{2} \\ 4\sqrt{5} = c[/tex]
