Réponse :
Bonjour,
Exo 1
1. 4x-3=2x+9 --> 4x-2x = 9+3 --> 2x=12 --> x=12/2 = ....
2. 6x-9=3x+4 --> 6x-3x=4+9-->3x=13 -->x=....
3. 8-(3x+2) = 5x-5 -->8-3x-2=5x-5-->6-3x=5x-5 --> 6+5=5x+3x -->11=8x--> x=....
4. 7+2(3-x) = 4x-1 -->7+6-2x=4x-1 -->13-2x=4x-1 --> 13+1=4x+2x-->14=6x--> x=.....
Exo 2
1. 4x - 5(3-2x) = 4 – (2x-7) --> 4x-15+10x=4-2x+7 -->14x-15=11-2x-->14x+2x=11+15-->16x=26-->x=.....
2. 9x-3(4-3x) = 2 – (35-3(4-2x)) --> 9x-12+9x= 2-(35-12+6x) -->18x-12=2-35+12-6x-->18x-12= -21 – 6x--> 18x+6x = -21+12 -->24x=-9 --> x = ....
3. 5x-3(7-4(3-2x)) = 5(3-x)-4 --> 5x-3(7-12+8x) = 15-5x-4 --> 5x-3(-5+8x)=11-5x --> 5x+15-24x=11-5x--> -19x+15=11-5x 15-11 = -5x+19x --> 4=14x --> x=...
4. 3x-5(3-2x) = 6x-15 --> 3x-15+10x=6x-15 --> 13x-15=6x-15 --> 13x-6x=-15+15--> 7x=0 --> x=....
Exo 3
1. [tex]\frac{3x}{2} = \frac{1}{5} --> 3x = \frac{1}{5} *2 --> 3x=\frac{2}{5} --> x=\frac{\frac{2}{5} }{3} --> x=\frac{2}{5} *\frac{1}{3} --> x=.....[/tex]
2. [tex]0=-3-2x --> 2x=-3 --> x=....[/tex]
3.
[tex]\frac{x-4}{3} = \frac{x+3}{4} --> \frac{x-4}{3} - \frac{x-3}{4} = 0 --> \frac{4*(x-4)}{3*4} - \frac{3*(x-3)}{4*3} =0 --> \frac{4*(x-4)}{12} - \frac{3*(x-3)}{12} =0 --> \frac{4x-16}{12} - \frac{3x-9}{12} =0 --> \frac{4x-16-3x-9}{12} =0 --> \frac{x-25}{12} =0 --> x-25=0 --> x=....[/tex]
Je te laisse finir les calculs
