Two lines are intersected by a third line. two horizontal parallel lines are intersected by a third line. the third line intersects the top line and forms 4 angles. labeled clockwise, from uppercase left, the angles are 1, 2, 4, 3. the third line intersects the bottom line and forms 4 angles. labeled clockwise, from uppercase left, the angles are 5, 6, 8, 7. if angle2 is-congruent-to angle6, which must be true about angle2?