bonsoir
Kader
2 x + 4
Sophie = 3 x - 7
1. 2 x + 4 = 3 x - 7
2 x - 3 x = - 7 - 4
- x = - 11
x = 11
2. 2 x + 4 = - 3 x + 7
2 x + 3 x = 7 - 4
5 x = 3
x = 3 /5
3. ( 2 x + 4 ) ( 3 x - 7 ) = 0
x = - 4/2 = - 2 ou 7/3
4. ( 2 x + 4 )² = ( 3 x - 7 ) ²
( 2 x + 4 )² - ( 3 x - 7 )² = 0
( 2 x + 4 + 3 x - 7 ) ( 2 x + 4 - 3 x + 7 ) = 0
( 5 x - 3 ) ( - x + 11 ) = 0
x = 3/5 ou 11
