bonjour
3 x = 0
x = 0
3 x - 12 = 0
3 x = 12
x = 4
6 x + 42 = 0
6 x = - 42
x = - 7
3 x ( x - 5 ) = 0
x = 0 ou 5
5 ( x + 4) + ( x - 7 ) ( x + 4 ) = 0
( x + 4 ) ( 5 + x - 7 ) = 0
( x + 4 ) ( x - 2 ) = 0
x = - 4 ou 2
25 x² - 9 = 0
( 5 x - 3 ) ( 5 x + 3 ) = 0
x = 3/5 ou - 3 /5
16 x² - 56 x + 49 = 0
( 4 x - 7 ) ² = 0
x = 7/4