I'm completely lost and don't know what to do

Answer:
[tex] x = 3 \sqrt{2}[/tex]
Step-by-step explanation:
[tex] \sin \: 45 \degree = \frac{x}{6} \\ \frac{1}{ \sqrt{2} } = \frac{x}{6} \\ x = \frac{6}{ \sqrt{2} } \\ x = \frac{6 \sqrt{2} }{2} \\ x = 3 \sqrt{2} \\ [/tex]