http://img33.imageshack.us/img33/335...ialangles6.jpg
Please explain. Thanks
http://img33.imageshack.us/img33/335...ialangles6.jpg
Please explain. Thanks
Let $\displaystyle O$ be the centre of the circle. The information $\displaystyle \widehat{CD}=55^\circ$ tells you that $\displaystyle \angle COD=55^\circ.$ Now use the theorem that the angle at the centre is twice the angle at the circumference to find $\displaystyle \angle DBC.$ Can you see how to continue the problem from there?