iran-konkur 2015 Q126

iran-konkur · Other · konkur-riazi_1394 Not Maths
126- In isosceles triangle $ABC$ ($AB = AC$), point $O$ is the center of the circle circumscribed about $AC$ that cuts $BC$ at point $B$ such that $BC$ is tangent to this circle at $D$. Triangle $OCD$ is:
  • [(1)] isosceles
  • [(2)] right-angled
  • [(3)] right-angled and isosceles
  • [(4)] indeterminate
\textbf{126-} In isosceles triangle $ABC$ ($AB = AC$), point $O$ is the center of the circle circumscribed about $AC$ that cuts $BC$ at point $B$ such that $BC$ is tangent to this circle at $D$. Triangle $OCD$ is:

\begin{itemize}
\item[(1)] isosceles
\item[(2)] right-angled
\item[(3)] right-angled and isosceles
\item[(4)] indeterminate
\end{itemize}