1) -7x+9=4-2x
-9x+9=4
-9x=-5
x=-5/-9
2)-2(2-3x)+5<7-5(x+3)
-4+6x+5<7-5x-15
-4+11x+5<7-15
11x+5<11-15
11x<11-20
11x<-9
x<-9/11
3)(x-5)(1-2x)=<(2x+3)(1-x)
x-2x^2-5+10x=<2x-2x^2+2-3x
x-5+10x=<2x+2-3x
11x-5=<-1x+2
12x-5=<2
12x=<7
x=<7/12
4)-7x+2<3x-8
-10x+2<-8
-10x<-10
x<10/-10
5)7x-2<x+8
6x-2<8
6x<6
x<1
6)-5x+4=x-2
-6x+4=-2
-6x=-6
x=-1
7)(x-3)(2-x)=-2x^2+4x
2x-x^2-6+3x=-2x^2+4x
2x-6+3x=4x
5x-6=4x
6=-x
-6=x
8)-3(1-2x)=<9
-2+6x=<9
6x=<11
x=<5
9)2-7x>4(x-1)
2-7x>4x-4
2>11x-4
-2>11x
-2/11>x
Je ne suis pas sur de tous mes calculs vérifient les :)
