# Chapter 5 Lines and Angles Class 7 Notes Maths

Chapter 5 Lines and Angles Class 7 Notes Maths is available on this page that will be make sure that a student has understood the specifics of every chapter in clear and precise manner. Class 7 Maths Revision Notes will help the students to recall information with more precision and faster. NCERT Notes becomes a vital resource for all the students to self-study from NCERT textbooks carefully. You will findÂ NCERT Solutions for Class 7 Chapter 5 Maths through which you will be able to solve the difficult problems in a given in exercise.

Recall

â€¢ A Point means a location.

â€¢ A line is a straight that extends endlessly in both directions.

â€¢ A line segment is the part of a line between two points.

â€¢ A ray is part of a line that starts at one point and extends endlessly in another direction.

â€¢Â An angle is formed when lines or line segments meet.

Related Angles

â€¢ When the sum of the measures of two angles is 90Â°, the angles are called complementary angles.

â€¢ Whenever two angles are complementary, each angle is said to be the complement of the other angle.

â€¢ When the sum of the measures of two angles is 180Â°, the angles are called Supplementary angles.

â€¢Â When two angles are supplementary, each angle is said to be the supplement of the other.

â€¢ Two angles with a common vertex and common arm but no common interior points are called Adjacent angles.

â€¢ These angles are such that:
(i) they have a common vertex;
(ii) they have a common arm; and
(iii) the non-common arms are on either side of the common arm.

â€¢ A linear pair is a pair of adjacent angles whose non-common sides are opposite rays.

â€¢ Vertically Opposite Angles: Two angles formed by two intersecting lines having no common arm. When two lines intersect, the vertically opposite angles so formed are equal.

Pair of Lines

â€¢ Intersecting Lines: Two or more lines that have one and only one point in common. The common point where all the intersecting lines meet is called the point of intersection.

â€¢Â A line that intersects two or more lines at distinct points is called a transversal.

â€¢ Parallel lines: Two lines in the same plane that are at equal distance from each other and never meet.

â€¢ Alternate interior angle : The pair of angles on opposite sides of the transversal but inside the two lines are called alternate interior angles.

â€¢ Alternate exterior angle : The pair of angles on the opposite sides of the transversal but outside the two lines
are called alternate exterior angles

â€¢ When two lines are intersected by a transversal, eight angles are formed.

Interior angles: âˆ 3, âˆ 4, âˆ 5, âˆ 6
Exterior angles: âˆ 1, âˆ 2, âˆ 7, âˆ 8
Pairs of corresponding angles: âˆ 1 and âˆ 5, âˆ 2 and âˆ 6, âˆ 3 and âˆ 7, âˆ 4 and âˆ 8
Pairs of Alternate interior angles: âˆ 3 and âˆ 6, âˆ 4 and âˆ 5
Pairs of Alternate exterior angles: âˆ 1 and âˆ 8, âˆ 2 and âˆ 7
Pairs of interior angles on the same side of the transversal: âˆ 3 and âˆ 5, âˆ 4 and âˆ 6.

Transversal of parallel lines

â€¢ If two parallel lines are intersected by a transversal, each pair of:
(i) corresponding angles are congruent
(ii) alternate interior angles are congruent
(iii) alternate exterior angles are congruent
(iv) interior angles on the same side of the transversal are supplementary.
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