In the given figures below, decide whether l is parallel to m.

(i) 126° + 44° = 170°
l ||m because sum of interior opposite angles should be 180.
(ii) 75° + 75° = 150°
l ||m because sum of angles does not obey the property of parallel lines.
(iii) 57° + 123° = 180°
l ||m due to supplementary angles property of parallel lines.
(iv) 98° + 72° + 170°
l is not parallel to m because sum of angles does not obey the property of
parallel lines.

Class 7 Maths Chapter 5 Exercise 5.2

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