bonjour
a) 2 ( 3 x - 1 ) - 4 ( 1 -x ) = 5 ( x + 3)
= 6 x - 2 - 4 + 4 x = 5 x + 15
= 10 x - 5 x = 15 + 6
5 x = 21
x = 21/5
b) ( 3 x - 2) ( x + 3) = 2
(3 x - 2 - 2 x + 6 ) / x - 3 = 0
( x + 4)/ ( x - 3) = 0
x - 3 = 0 ⇔ x = 3
x + 4 = 0 ⇔ x = - 4
c) ( x - 3 )² = 16
( x - 3 ) ² - 16 = 0
( x - 3 - 4) ( x - 3 + 4) = 0
( x - 7) ( x + 1) = 0 ⇔ x = 7 ou - 1
continue
