In

∠ABC + ∠ACB + ∠CAB = 180^o

5y + 3y + x = 180^o

8y + x = 180^o (i)

∠ABC + ∠CBD = 180^o (Linear pair)

5y + 7y = 180^o

y = 15^o

Putting values of y in (i), we get

8 * 15 + x^o = 180^o

x = 60^o