Given that,

l ‖ m

Let,

∠1 = 3y

∠2 = 2y + 25^o

∠3 = x + 15^o

∠1 = ∠2 (Alternate angle)

3y = 2y + 25^o

y = 25^o

∠2 = ∠3 (Vertically opposite angle)

x + 15^o = 2 (25^o) + 25^o

x = 60^o