Bonsoir, voici une série d'équations que j'ai à faire pour demain mais je n'y arrive pas. Merci d'avance a) 3x - 1 = 0 a) 2(3 + 2x) = 5x +.12 b) 2 - 3x = 0 b) 3

Réponse :

Explications étape par étape

Bonjour

a) 3x - 1 = 0

3x = 1

x = 1/3

a) 2(3 + 2x) = 5x +.12

6 + 4x = 5x + 12

6 - 12 = 5x - 4x

-6 = x

x = -6

b) 2 - 3x = 0

3x = 2

x = 2/3

b) 3x – 4 = 5(x - 1)

3x - 4 = 5x - 5

-4 + 5 = 5x - 3x

1 = 2x

x = 1/2

c) 5 + 4x = 0

4x = -5

x = -5/4

c) 2(3y - 2) = -6y + 1

6y - 4 = -6y + 1

6y + 6y = 1 + 4

12y = 5

y = 5/12

d) 3x + 5 = -2

3x = -2 - 5

x = -7/3

e) 7x - 5 = 12

7x = 12 + 5

x = 17/7

f) 3x – 3 = 6x + 1

-3 - 1 = 6x - 3x

-4 = 3x

x = -4/3

d) 4(4y + 1) = 6(2y - 1)

16y + 4 = 12y - 6

16y - 12y = -6 - 4

4y = -10

y = -10/4

y = -5/2

e) 2(5x - 3) = 4(x – 5)

10x - 6 = 4x - 20

10x - 4x = -20 + 6

6x = -14

x = -14/6

x = -7/3

f) 3-2(x+2) = 2(x + 1)

3 - 2x - 4 = 2x + 2

-1 - 2 = 2x + 2x

-3 = 4x

x = -3/4

g) x + 3(x - 1) = 2x - 3

x + 3x - 3 = 2x - 3

4x - 2x = -3 + 3

2x = 0

x = 0

h) 7x-(5x + 3) = 5(x-3)+2

7x - 5x - 3 = 5x - 15 + 2

2x - 3 = -13 + 5x

13 - 3 = 15x - 2x

10 = 13x

x = 10/13

i) 7(x + 2) - 3 = 25-(3x + 4)

7x + 14 - 3 = 25 - 3x - 4

7x + 3x = -11 + 21

10x = 10

x = 10/10

x = 1

g) 3 - 6x = 15x + 16

3 - 16 = 15x + 6x

-13 = 21x

x = -13/21

h) 5x + 1 =-3x +11

5x + 3x = 11 - 1

8x = 10

x = 10/8

x = 5/4

i) 5 - 2x = 5x + 5

5 - 5 = 5x + 2x

0 = 7x

x = 0

j) 4y + 3(4y - 2) = 3(y + 1)

4y + 12y - 6 = 3y + 3

16y - 3y = 6 + 3

13y = 9

y = 9/13

j) -3x – 1 = 8 - 2x​

-1 - 8 = 3x - 2x

x = -9