Lines and Angles
(NCERT Ex. 6.2 and Q & A from CBSE papers)
1. Corresponding angles axiom: If a transversal intersects two parallel lines, then each pair of corresponding angles is equal.
2. If a transversal intersects two lines such that a pair of corresponding angles is equal, then the two lines are parallel to each other.
3. If a transversal intersects two parallel lines, then each pair of alternate interior angles is equal.