There are two equal sides of 8, which means this is an isosceles triangle. With an isosceles triangle, there are also two equal angles (30° each in this case). If angle C equals 30°, then angle B also equals 30°. Subtract angles B and C from the total degrees in a triangle.
Triangles Degrees= 180° total
Find angle A: = total triangle degrees - < B - < C = 180° - 30° - 30° = 120°