Statement
If a transversal intersects two parallel lines, then each pair of alternate angles are equal.

Given:
AB||CD and EFGH is a transversal.
To prove:


Proof:
(Vertically opposite angles)

From (i) and (ii),

Theorem 2 |
If a transversal intersects two parallel lines, then each pair of alternate angles are equal.

AB||CD and EFGH is a transversal.


(Vertically opposite angles)

From (i) and (ii),

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