Réponse :

Explications étape par étape

a)(2x+1)(4x-1) = 0

On a 2x +1 =0 ==> 2x = -1 ==> x= -1/2

4x-1 =0 ==> 4x = 1 ==> x = 1/4

b)(2x-9) = 0 ==> x= 9/2

  -x-2 = 0 ==> x=-2

c) 3x - 5 = 0 ==> x =5/3

   8-2x =0  ==> x = 8/2 =4

d) 10-4x = 0 ==> x =10/4 = 5/2

Réponse :

20/

a. (2x + 1)(4x - 1) = 8x² - 2x + 4x - 1 = 8x² + 2x - 1

b. (2x - 9)(-x - 2) = -2x² - 4x + 9x + 18 = -2x² + 5x + 18

c. (3x - 5)(8 - 2x) = 24x - 6x² - 40 + 10x = -6x² + 34x - 40

d. (10 - 4x) X 7 = 70 - 28x

Explications étape par étape