\(\begin{aligned} A r e a &=\frac{1}{2} \cdot a \cdot b \cdot \sin C \\ 28 &=\frac{1}{2} \cdot 8 \cdot 9 \cdot \sin C \\ \sin C &=\frac{28 \cdot 2}{8 \cdot 9} \\ C &=\sin ^{-1}\left(\frac{28 \cdot 2}{...\(\begin{aligned} A r e a &=\frac{1}{2} \cdot a \cdot b \cdot \sin C \\ 28 &=\frac{1}{2} \cdot 8 \cdot 9 \cdot \sin C \\ \sin C &=\frac{28 \cdot 2}{8 \cdot 9} \\ C &=\sin ^{-1}\left(\frac{28 \cdot 2}{8 \cdot 9}\right) \approx 51.06^{\circ} \end{aligned}\) \(\begin{aligned} \text {Area} &=\frac{1}{2} \cdot c \cdot b \cdot \sin A \\ 1.7 &=\frac{1}{2} \cdot c \cdot 4 \cdot \sin 12^{\circ} \\ c &=\frac{1.7 \cdot 2}{4 \cdot \sin 12^{\circ}} \approx 4.09 \end{aligned}\)
