Répondre :
c'est chaque fois la règle du produit nul , tu obtiens la solution en égalant chaque facteur à 0
Ainsi:
(x+1)(x-8)=0 => x+1 = 0 => x = -1 et x-8 = 0 => x = 8
.(5x - 3) (6+x) = 0 => x = 3/5 et x = -6
(11-8x)(3x+7) =0 => x = 11/8 et x = -7/3
(7-x)(x-7) = 0 => x = 7
2x(3x+2) (3x-1) = 0 => x = 0 et x = -2/3 et x = 1/3
Ainsi:
(x+1)(x-8)=0 => x+1 = 0 => x = -1 et x-8 = 0 => x = 8
.(5x - 3) (6+x) = 0 => x = 3/5 et x = -6
(11-8x)(3x+7) =0 => x = 11/8 et x = -7/3
(7-x)(x-7) = 0 => x = 7
2x(3x+2) (3x-1) = 0 => x = 0 et x = -2/3 et x = 1/3