bonjour
x² - 5 x = 0
x ( x - 5 ) = 0
x = 0 ou 5
- 3 x² + x = 0
x ( - 3 x + 1 ) = 0
x = 0 ou 1/3
4 x² = 28 x
4 x² - 28 x = 0
4 x ( x - 7 ) = 0
x = 0 ou 7
( 2 x - 1 ) ( x + 3 ) + ( x + 5 ) ( 2 x - 1 ) = 0
( 2 x - 1 ) ( x + 3 + x + 5 ) = 0
( 2 x - 1 ) ( 2 x + 8 ) = 0
x = 1/2 ou - 4
5 x ( 3 x + 2 ) = ( 3 x + 2 )²
5 x ( 3 x + 2 ) - ( 3 x + 2 )² = 0
( 3 x + 2 ) ( 5 - 3 x - 2 ) = 0
( 3 x + 2 ) ( - 3 x + 3) = 0
x = - 2/3 ou 1
