Question

prove that if two line intersect each other then the vertically opposite angles are equal

Answer 1

Given two lines AB and CD intersect each other at the point O.
To prove: ∠1 = ∠3 and ∠2 = ∠4
Proof:
From the figure, ∠1 + ∠2 = 180° [Linear pair] → (1)
∠2 + ∠3 = 180° [Linear pair] → (2)
From (1) and (2), we get
∠1 + ∠2 = ∠2 + ∠3
∴ ∠1 = ∠3
Similarly, we can prove ∠2 = ∠4 also.

Answer 2

I think it help u............