pouvez vous m'aider svp Exercice 2 :
Résoudre les équations suivantes :
12x - 4 = 20x + 28
(3x - 4X2x + 5) = 0
2( 3 x - 4)-(2x + 5) = 0
(5x - 7)2 = 0
x2 + 20x + 100=0​


Sagot :

ANASAG

Réponse:

12x -4 = 20x +28

12 -20x = 28 +4

-8x = 32

-8x/-8 = 32/-8

x = -4

(3x -4×2x +5) = 0

(3x -8x +5) = 0

-5x +5 = 0

-5x = -5

-5x/-5 = -5/-5

x = 1

2(3x-4) - (2x+5) = 0

6x -8 -2x -5 = 0

6x -2x = 8 +5

4x = 13

4x/4 = 13/4

x = 13/4

(5x-7)2 = 0

10x -14 = 0

10x = 14

10x/10 = 14/10

x = 14/10

x = 7/5

2x +20x +100 = 0

22x = -100

22x/22 = -100/22

x = -100/22

x= -50/11