Bonjour une personne pour m'aider a faire mes exercices de maths ? Merci

Réponse :

1ere ligne

a. 7x -6 = 4 -3x => 7x = 4 + 6 -3x => 7x + 3x = 10 => 10x = 10 => x = 10/10 = 1

b. 12 - a = 18 - 3a => 12 = 18 - 3a + a => 12 - 18 =  - 3a + a => -6 = -2a = -6/-2 = 3 = a

2eme ligne

a. -t -4 = 8 + 7t => -4 = 8 + 7t + t => -4 - 8 = 8t => -12 = 8t = -12/8 = -1,5 =t

b. 13x + 11 = 8x +28 => 13x = 8x + 28 - 11 => 13x - 8x = 17 => 5x = 17 =>x = 17/5 = 3,4

7X-6=4-3X

7X+3X=6+4

10X÷10=10÷10

X=1

12-a=18-3a

-a+3a=18-12

2a÷2=6÷2

A=3

-t-4=8+7t

-t-7t=8+4

-8t÷-8=12÷-8

T=-1,5

13X+11=8X+28

13X-8X=28-11

5X÷5=17÷5

X=3,4