Bonjour,
Ligne 1 : (7x+10) + (4x+1) + (-3x+2) + (x-6) = 9x+7
Ligne 2 :(6x+1) + (-2x-9) + (-3x-5) + (4x-7) = 5x-20
Somme des 2 lignes : (9x+7) + (5x-20) = 14x-13
Colonne 1 : (7x+10) + (6x+1) = 13x+11
Colonne 2 : (4x+1) + (-2x-9) = 2x-8
Colonne 3 : (-3x+2) + (-3x-5) = -6x-3
Colonne 4 : (x-6) + (4x-7) = 5x-13
Somme des 4 colonnes : (13x+11) + (2x-8) + (-6x-3) + (5x-13) = 14x-13
