Bonjour,
1)
7n = -3
n= -3/7
2)
Équation produit nul, 2 solutions
x-2 = 0 => x=2
2x+3 = 0 => 2x= -3 => x= -3/2
3)
Equation produit nul
2(x+3)= 0 => 2x+6 =0 => 2x= -6 => x= -6/2 = -3
x-7 = 0 => x = 7
4)
3x² = 6x
x² = 6x/3 = 2x
x= √2x
5)
x² = 9
x= √9= 3
6)
20x+20
distributivité
7)
(4x+6) x= 4x² +6x
8)
14x² +14x +14x + 14 = 14x² +28x + 14
double distributivité
9)
ab+ ac
distributivité
