Angle Congruency
Two angles are equal if any of the following conditions are true:
- They are vertical angles.
- The left side of one is parallel to the left side of the other, and the right side of one is parallel to the right side of the other (the left and right sides are as seen from the vertex, where the two sides meet).
- The left side of one is perpendicular to the left side of the other, and the right sides are likewise perpendicular.
