Question

please explain this question because tommorow is my exam

Answer 1

heya!!

refer to given attachment please

Answer 2

Hey,

Check this out →

→ ∠x + ∠y + ∠z = 180°

=> ∠x + ( 180° - ∠EBC ) + ( 180° - ∠DCB ) = 180°

But, ∠EBC = 2∠OBC and ∠DCB = 2∠OCB

=> ∠x + ( 180° - 2∠OBC ) + ( 180° - 2∠OCB ) = 180°

=> ∠x + 180° - 2( ∠OBC + ∠OCB ) = 0°

But, ∠OBC + ∠OCB = 180° - ∠BOC [ in Δ OBC ]

=> ∠x + 180° - 2( 180° - ∠BOC ) = 0°

=> ∠x - 180° + 2∠BOC = 0°

=> ∠BOC =  90° - ( ∠x / 2 )

Hope it helped ^_^