Angle XOY being 100º, and the three angles of a triangle totalling 180º, angles YXO and XYO must equal 40º.
Imbombo engu XOY emalunga nekhulu lamanqanaba kwaye iineembombo ezintathu zonxantathu olingana nekhulu elinamashumi asobhozo zamanqanaba, imbombo uYXO noXYO mabalingane namashumi amane amanqanaba.