Question

Rezolvați inecuația:a)3x_<21
b)-5x<35
c)3x+6_<3
d)2-6x>14
e)3-9x_<1-x
f)5(x+4)<2(4x-5)

Answer 1

3x=<21=>x=<7=>x apartine (-∞;7]
-5x<35=>x>-7=>x apartine (-7;+∞)
3x+6=<3=> 3x=<-3=>x=<-1=> x apartine (-∞; -1]
2-6x>14=> -6x>12=>6x<-12=>x<-2=> x apartine (-∞;-2)
3-9x=<1-x=> 3-10x=<1=>-10x=<-2=>10x>=2=>x>=1/5=> x apartine [1/5; +∞)
5(x+4)<2(4x-5)=>5x+20<8x-10=> 20<3x-10=>30<3x=>10 x apartine (10; +∞)