Réponses

2014-01-19T22:17:04+01:00
3x-4=2x+5
3x-2x=5+4
x=9

4(3x-1)=9x+2
12x-4=9x+2
12x-9x=2+4
3x=6
x=2

x+7x-12=14-3x+7
8x-12= -3x+21 8x+3x=21+2 11x= 33 x=33/11=3
  • Utilisateur Brainly
2014-01-19T22:20:41+01:00
1/ a) 3x-4=2x+5
x=9
b) 4(3x-1)=9x+2
12x-4=9x+2
3x=6
x=6/3
x=2

2/ x+7x-12=14-3x+7
8x-12=21-3x
8x=33-3x
5x=33
x=33/5

3/ 4x-2=10+2x
6x=12
x=12/6
x=2

4/ 1) x+1.5=5.5
x=4
2) 8x=32
x=32/8
x=4
3) 4x+10=36
4x=26
x=26/4 ou x=6.5