[tex]\it \widehat N=180^o-(105^o+30^o)=180^o-135^o=45^o \Rightarrow \Delta AMN-dr.isoscel \Rightarrow \\ \\ \Rightarrow AN=AM\ \ \ \ \ \ \ (1)\\ \\ T.\angle\ 30^o\ \ pentru\ \ \Delta MAP \Rightarrow AM=\dfrac{MP}{2}=\dfrac{18}{2}=9\ cm\ \ \ \ \ (2)\\ \\ \\ (1),\ \ (2)\ \Rightarrow AN=9\ cm[/tex]
