Question

if two lines are intersected by a transversal such that the pair of interior angle on the same side of the transversal are supplementary then prove that the lines are parallel

Answer 1

Dear Student
1.Drawn two lines AB and CD (one below the other)and taking EF as the transversal.

2. Now marking a pair of interior angles as /_1 and other as /_ 6.

3. /_1 = /_3 (vertically opposite angles),/_7 = 180-/_6 (linear pair) which eventually means /_7 is corresponding to /_3. Corresponding angles are equal only if lines are parallel. So,AB||CD.Hence proved.
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