Answer:
120.8degrees
Explanation:
To get the angle C, we will use the cosine rule formula as shown;
[tex]c^2=a^2+b^2-2ab\cos C[/tex]
Given the following;
a = 11
b = 12
c = 20
Substitute into the formula above;
[tex]\begin{gathered} 20^2=11^2+12^2-2(11)(12)\cos C \\ 400\text{ = 121 + 144 - }264\cos C \\ 400\text{ = }265-264\cos C \\ 400\text{ - 265 = -264cosC} \\ 135\text{ = -2}64\cos C \\ \text{CosC = -}\frac{135}{264} \\ \text{CosC =-}0.5114 \\ C=cos^{-1}(-0.5114) \\ C\text{ =}120.75 \\ C\approx120.8^0 \end{gathered}[/tex]
Hence the measure of mes
