Answer:
Length of side a is 7.8
Option C is correct
Explanation:
Given b=10, c=11 and A = 43°, we need to find the length of a.
Using the Law of Cosines
a^2 = b^2+c^2-2bccosA
a^2 =(10)^2+(11)^2-2(10)(11)(cos 43°)
a^2 = 100+121-2(110)(0.7313)
a^2=100+121-160.886
a^2=221-160.886
a^2=60.114
a=√60.114
a= 7.75
a≈ 7.8
So, length of side a is 7.8
Option C is correct