Answer:
[tex]C=125.0^\circ[/tex]
Step-by-step explanation:
In a triangle:
b=3 ; a=9 ; c=11
We want to determine the value of Angle C.
Since we are given three sides of the triangle, we use the Law of Cosines to find any of the angles.
[tex]c^2=a^2+b^2-2ab\cos C\\11^2=9^2+3^2-2(9)(3)\cos C\\11^2-(9^2+3^2)=-2(9)(3)\cos C\\31=-54\cos C\\\cos C=-\dfrac{31}{54} \\C=\arccos (-\frac{31}{54}) \\C=125.0^\circ$ (to the nearest tenth)[/tex]
