Решебник по геометрии 9 класс Мерзляк Задание 179

\[1)\ n = 6:\]

\[S_{6} = (6 - 2) \bullet 180{^\circ} =\]

\[= 4 \bullet 180{^\circ} = 720{^\circ}\]

\[a = \frac{1}{6} \bullet S_{6} = \frac{1}{6} \bullet 720{^\circ} = 120{^\circ}.\]

\[Ответ:\ \ 120{^\circ}.\]

\[2)\ n = 9:\]

\[S_{9} = (9 - 2) \bullet 180{^\circ} =\]

\[= 7 \bullet 180{^\circ} = 1260{^\circ}\]

\[a = \frac{1}{9} \bullet S_{9} = \frac{1}{9} \bullet 1260{^\circ} = 140{^\circ}.\]

\[Ответ:\ \ 140{^\circ}.\]

\[3)\ n = 15:\]

\[S_{15} = (15 - 2) \bullet 180{^\circ} =\]

\[= 13 \bullet 180{^\circ} = 2340{^\circ}\]

\[a = \frac{1}{15} \bullet S_{15} = \frac{1}{15} \bullet 2340{^\circ} = 156{^\circ}.\]

\[Ответ:\ \ 156{^\circ}.\]