In the given figure, if MN and PQ are parallel, find the value of (∠X + ∠Y).
MN and PQ are parallel lines and PN is transversal.
∴ ∠QPN=∠MNP
[Alternate interior angles]
So, ∠QPN=X=30∘
Now, ∠ Y=∠PQM + ∠QPN
[Exterior angle property]
⇒∠Y=45∘ + 30∘ ⇒∠Y=75∘
So, value of ∠X + ∠ Y=30∘+75∘=105∘