更新时间2022-03-19 12:32:39
(1)
3x-2<8,3x<2+8=10,x<10/3
2x-1>2,2x>1+2=3,x>3/2
不等式组解集:3/2<x<10/3
(2)
5-7x≥2x-4,-7x-2x≥-5-4,-9x≥-9,x≤1
1-3(x-1)/4<0.5,4-3(x-1)<2,
4-3x+3<2,-2x<2-7=-5,x>5/2
不等式组解集:∅
(3)2x<1-x≤x+5
2x<1-x,2x+x<1,3x<1,x<1/3
1-x≤x+5,-x-x≤5-1,-2x≤4,x≥-2
不等式组解集:-2≤x<1/3
(4)
3(1-x)<2(x+9),3-3x<2x+18
-3x-2x<18-3,-5x<15,x>-3
.
(x-3)/0.5-(x+4)/0.2≤-14
2(x-3)-5(x+4)≤-14
2x-6-5x-20≤-14
-3x≤26-14=12
x≥-4
不等式组解集:x>-3