We have the following:
[tex]\begin{gathered} \frac{5.7}{\sin x}=\frac{7}{\sin 66^{\circ\: }} \\ \sin x=\frac{57\cdot\sin 66^{\circ}}{70} \\ \sin x=\frac{57\cdot0.913}{70} \\ x=\sin ^{-1}(0.743) \\ x=48.06\cong48^{\circ\: } \end{gathered}[/tex]
Therefore, the answer is 48°
