Triangle Length Using Law of Cosines

In triangle ABC, let side AB = 10 units, side AC = 14 units, and angle A = 40 degrees. Use the Law of Cosines to find the length of side BC.

Recall that the Law of Cosines states that for any triangle:

$$c^2 = a^2 + b^2 - 2ab \cdot \cos(C)$$

where $c$ is the side opposite angle C, and $a$ and $b$ are the other two sides.