RD Sharma Class 7 Solutions Chapter 14 Lines and Angles
A Line that intersects two or more given lines at distinct points is called a transversal to the given lines.
Lines in a plane are parallel if they do not intersect when produced indefinitely in either direction.
The distance between two parallel lines is the same everywhere and is equal to the perpendicular distance between them.
If two parallel lines are intersected by a transversal then
- Pairs of alternate (interior and exterior) angles are equal
- Pairs of corresponding angles are equal
- Interior angels on the same side of the transversal are supplementary
If two lines are intersected by a transversal, then they are parallel if any one of the following is true:
- The angles of a pair of corresponding angles are equal.
- The angles of a pair of alternate interior angles are equal.
- The angles of a pair of interior angles on the same side of the transversal are supplementary