Question

prove theorem 6.5 of class 9th​

Answer 1

Answer: please mark brainliest

Step-by-step explanation:

A transversal EF intersects two lines AB and CD at P and Q respectively.

To Prove: AB ||CD

Proof: ∠1 + ∠2 = 180° ………..equation (i) (Given)

∠1 + ∠3 = 180° …………..equation (ii) (Linear Pair)

From equations (i) and (ii)

∠1 + ∠2 = ∠1 + ∠3

Or, ∠1 + ∠2 - ∠1 = ∠3

Or, ∠2 = ∠3

But these are alternate interior angles. We know that if a transversal intersects two lines such that the pair of alternate interior angles are equal, then the lines are parallel.

Hence, AB║CD Proved.

Answer 2

hope it will help you....ty ^_^