Length of Side in Triangle Using Law of Sines

In triangle ABC, angle A is twice that of angle B, and angle C is 30 degrees. Find the length of the side opposite angle A, given that the side opposite angle B is 10 units.

Use the Law of Sines, which states that:

where $A$, $B$, and $C$ are the angles, and $a$, $b$, and $c$ are the lengths of the sides opposite those angles, respectively. Note that the angles of a triangle sum to 180 degrees.