Answer:
7.9
Step-by-step explanation:
k^2 = 3.7^2+5.2^2-2(3.7)(5.2)\cos 124
k
2
=3.7
2
+5.2
2
−2(3.7)(5.2)cos124
Plug in values.
k^2 = 13.69+27.04-2(3.7)(5.2)(-0.559193)
k
2
=13.69+27.04−2(3.7)(5.2)(−0.559193)
Square and find cosine.
k^2 = 13.69+27.04+21.51774
k
2
=13.69+27.04+21.51774
Multiply.
k^2 = 62.24774
k
2
=62.24774
Add.
k=\sqrt{62.24774} \approx7.89 \approx7.9
k=
62.24774
≈7.89≈7.9
