Выполни задание

Вычисли градусную меру угла \(BCD\) .

Решение. \(\angle A+\angle ABD=\) [ ] \(\degree\) (по свойству [ ][ ]). \(\angle A=\angle ABD\) , так как \(\triangle ABD\) — [ ] (по [ ][ ][ ]). Следовательно, \(\angle ABD=72\degree :2=\) [ ] \(\degree\) , \(\angle DBC= \angle ABD=\) [ ] \(\degree\) , \(\angle C=\) [ ] \(\degree -(\) [ ] \(\degree +(\) [ ] \(\degree )=\) [ ] \(\degree\) .

Ответ: \(\angle BCD=\) [ ] \(\degree\) .