Graphes - degrés des sommets - propriétés - terminale maths expert

http://www.jaicompris.com/ What is a graph?:    • Les graphes - Définitions et vocabulaire d...   Objectives: Know and understand that the sum of the degrees of the vertices is equal to twice the number of edges. Know and understand that the number of vertices of odd degree in a graph is even. Exercise: A soccer tournament involves 5 teams. The organizer wants each team to play exactly 3 matches. Explain why this is impossible. Math lessons and exercises Tenth grade, expert math option