C^2=a^2+b^2-2abcosC
13^2=10^2+11^2-2×10×11×cos(°)
169=100+121-220cos(°)
220cos(°)=100+121-169
220cos(°)=52
cos(°)= 13/55
°=cos-1(13/55)
°=76.328°
I have no idea what this is asking honestly but i hope you figure it out
You can’t view the questions
Answer:
12.
Step-by-step explanation:
The side length = sqrt 9 = 3
so the perimeter = 4*3 = 12.