State the property that is used in each of the following statements?
(i) If a || b, then ∠1 = ∠5.
(ii) If ∠4 = ∠6, then a || b.
(iii) If ∠4 + ∠5 = 180°, then a || b

Explanation

(i) If a ∥ b, then `∠1 = ∠5`.


Property used here is Corresponding angles property in the above statement.


(ii) If `∠4 = ∠6`, then a ∥ b.



Property used here is Alternate interior angles property in the above statement.

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