Respuesta :

From definition:

[tex]\sin (angle)=\frac{\text{opposite side}}{\text{ hypotenuse}}[/tex]

From the picture:

[tex]\begin{gathered} \sin (45)=\frac{8}{h} \\ \frac{1}{\sqrt[]{2}}=\frac{8}{h} \\ h=8\cdot\sqrt[]{2} \end{gathered}[/tex]