NCERT Solutions for Class 7th Maths Chapter 5 Parallel and Intersecting Lines
Updated on 2026-09-08
About this chapter
When two lines intersect, four angles are formed. Linear pairs add up to 180° and vertically opposite angles are equal. If all four angles at a crossing are equal, each is 90° and the lines are perpendicular . Parallel lines lie in the same plane and never meet, however far they are extended. They are marked with matching arrow heads. A transversal cutting two lines makes 8 angles, with at most 4 different sizes. Corresponding angles are equal exactly when the two lines are parallel — this is the test for parallelism. For a transversal across parallel lines: alternate angles are equal, and interior angles on the same side add up to 180°.
- Across the Line
- Perpendicular Lines
- Between Lines
- Parallel and Perpendicular Lines in Paper Folding
- Paper Folding, and Notations
- Transversals and 5.6 Corresponding Angles
- Corresponding Angles
- Drawing Parallel Lines
- Alternate Angles
- Parallel Illusions
Exercises
- In-text Questions — Across the Line Page 106
- In-text Questions — Across the Line Page 107
- Figure it Out — Across the Line Page 108
- In-text Questions — Perpendicular Lines Page 108
- In-text Questions — Between Lines Page 109
- In-text Questions — Between Lines Page 110
- Activity 2 — Parallel and Perpendicular Lines in Paper Folding Page 111
- In-text Questions — Paper Folding, and Notations Page 112
- Figure it Out — Parallel and Perpendicular Lines in Paper Folding Page 113–114
- In-text Questions — Transversals and 5.6 Corresponding Angles Page 115
- Activity 3 — Corresponding Angles Page 116
- Activities 4 and 5 — Corresponding Angles Page 117
- In-text Questions — Drawing Parallel Lines Page 118–119
- Figure it Out — Drawing Parallel Lines Page 119
- In-text Questions — Alternate Angles Page 120
- Examples — Alternate Angles Page 120–122
- Figure it Out — Alternate Angles Page 123–125
- In-text Questions — Parallel Illusions Page 125