Question 1 Question 2 Question 3 Question 4 Question 5 Question 6 À propos
Hypothèses
  • AB || CD;
  • m∡AEB = 42°
  • ∆AEB est isocèle (AEBE)
Question
  • Montre que m∡ECD = 69°
Affirmations
Justifications
∠EAB ≅ ∠EBA
m∡EAB = m∡EBA = (180° - 42°) ÷ 2 = 69°
m∡ECD = m∡EBA = 69°