[m] ∠ AOB=\frac{1}{2}( ∪ AB+ ∪ CD)[/m]
[m] =2 ∠ AOB- ∪ CD=2*76 ° -32 ° =
2.
[m] ∠ DOC=\frac{1}{2}( 152 °- x)[/m]
[m]x=152 ° -2 ∠ DOC[/m]
[m]x=152 °-2\cdot 46 ° [/m]
[m]x=60 ° [/m]
3.
[m] ∠ DOC=\frac{1}{2}( x-28 °)[/m]
[m]x=2 ∠ DOC+28 ° [/m]
[m]x=2 \cdot 54 ° +28 ° [/m]
[m]x=136 ° [/m]