Respuesta :

Answer:

The measure of angle C is;

[tex]\measuredangle C=35.7^{\circ}[/tex]

Explanation:

Given the figure in the attached image.

To get angle C, we will need to first calculate the length of side a.

Applying cosine rule;

[tex]a=\sqrt[]{b^2+c^2-2bc\cos A}[/tex]

given;

[tex]\begin{gathered} b=12 \\ c=7 \\ A=55^{\circ} \end{gathered}[/tex]

substituting the given values;

[tex]\begin{gathered} a=\sqrt[]{12^2+7^2-2(12)(7)\cos 55} \\ a=9.83 \end{gathered}[/tex]

We can now solve for angle C;

[tex]\begin{gathered} \cos C=\frac{a^2+b^2-c^2}{2ab} \\ \text{substituting;} \\ \cos C=\frac{9.83^2+12^2-7^2}{2(9.83)(12)} \\ \cos C=0.81226 \\ C=\cos ^{-1}(0.81226) \\ C=35.7^{\circ} \end{gathered}[/tex]

Therefore, the measure of angle C is;

[tex]\measuredangle C=35.7^{\circ}[/tex]