bonjour
(AB)² = ( 4 + 2 )² + ( - 3 - 1 )² = 6² + ( - 4 )² = 36 + 16 = 52
(AC)² = (- 1 + 2 )² + ( - 4 - 1 )² = 1² + ( - 5 )² = 1 + 25 = 26
(BC)² = ( - 1 - 4 )² + ( - 4 + 3 )² = ( - 5 )² + ( - 1 )² = 25 + 1 = 26
le triangle est isocèle et rectangle
26 + 26 = 52