2. A triangle has the angle measures 40 degrees, 60 degrees, and x degrees. If the sum of the angle measures is equal to 180 degrees, which equation could be used to correctly solve for x? Mark all that apply. (2 Points)
1. X - 100 = 180
2. 180 = 40 + 60 + X
3. 100x = 180
4. X + 100 = 180