bonjour,
3 (2x-5)=5- (3x-7)
6x-15 = 5-3x+7
6x+3x = 12+15
9x = 27
x = 3
-3(2x-4)=5x+3(rac.carr)7
-6x+12 = 5x+3V7
-6x-5x = 3V7-12
-11x = 3V7-12
x = -3V7+12
(-4x-3)(5x+2)=0
équation^produit nul
-4x-3 =0
-4x =3
x =-3/4
5x+2 =0
finis
(2x-3)(4+7x)+(2x-3)(x+4)=0
on facto (2x-3) puis équation produit nul
(2x-3)(4+7x+x+4) =0
(2x-3)(8x+8) =0
8(2x-3)(x+1) =0
finis
3x(carré)-2x=7x
3x²-2x-7x =0
3x²-9x =0
3x(x-3) = 0
finis
(5x-7)(-3x+2)=(-3x+2)(2x-5)
(5x-7)(-3x+2)-(-3x+2)(2x-5) = 0 idem, factorise (-3x+2) puis = 0
X(carré)=25
x²-25 = 0 =a²-b² =(a-b)(a+b)
(x-5)(x+5) = 0
finis
X(carré)+4x=-4
x²+4x+4 = 0
(x+2)²= 0
x = ....
