Exercice 2: Résoudre les équations et inéquations suivantes : (5x - 1)(2-3x)=0 2x-4=1+3x 7x-8 > 4x+7 9x +14=7x + 42 3x ≤ 12

Réponse:

( 5x - 1 ) ( 2 - 3x ) = 0

revient à résoudre

5x - 1 = 0.

2 - 3x = 0

x = 1/5

x = 2/3

2x - 4 = 2 + 3x

2x - 4 - 3x = 1

- x -4 = 1

- x = 1 + 4

- x = 5

x = - 5

9x + 14 = 7x + 42

9x + 14 - 7x = 42

2x + 14 = 42

2x = 42 - 14

2x = 28

x = 28/2

x = 14

3x <= 12

x <= 12/3

x <= 4