Q.1 State the property that is used in each of the following statements?

(i) If a \(\parallel \) b, then \(\angle \)1 = \(\angle \)5
(ii) If \(\angle \)4 = \(\angle \)6, then a \(\parallel \) b
(iii) If \(\angle \)4 + \(\angle \)5 = 180°, then a \(\parallel \) b

(i) Given a \(\parallel \)
So, \(\angle \)1 = \(\angle \)5 (Pair of corresponding angles)
(ii) Given: \(\angle \)4 = \(\angle \)6
So, a \(\parallel \) b [If pair of alternate angles are equal, then the lines are parallel]
(iii) Given: \(\angle \)4 + \(\angle \)5 = 180°
So, a \(\parallel \) b [If sum of interior angles is 180°, then the lines are parallel]