• Using the law of cosines:
b² = c² + a² - 2ac CosB
b² = 5² + 6² - 2(6)(5) cos 60°
b² = 31
b = 5.568
• Using the law of sines:
[tex]\begin{gathered} \frac{b}{\sin\text{ B}}=\text{ }\frac{a}{\sin \text{ A}} \\ \\ \sin A\text{ =}\frac{\sin B\times a}{b} \\ \\ \sin A\text{ =}\frac{\sin 60\text{\degree x 6}}{5.568} \\ \\ A\text{ =68.869\degree} \end{gathered}[/tex]
°C = 180° - 60° - 68.869° = 51.131°
