NCERT CLASS 9 · MATHS
Lines and Angles
This original revision companion supports the official NCERT book; it does not replace it.
Focus
Use a labelled diagram to connect adjacent, vertically opposite, and transversal angles.
Common mistake
Never assume two lines are parallel unless it is given or proved.
10-minute routine
- Read the matching section in the official NCERT book ↗.
- Write three key ideas without looking.
- Take the Class 9 practice quiz ↗.
- Check your score in My Practice ↗.