It is not possible to determine the number of triangles that can be formed with the given parts because we do not have enough information. To uniquely determine a triangle, we need at least one side length and two angles (one of which must be the angle opposite the side length). In this case, we only have one side length (b=20) and two angles (A=50°, C=50°), which is not enough to determine the number of possible triangles.
