解下列不等式(过程)(1)-3x<-15 (2)2x+3>5 (3)2分之2+x≥3分之2x-1 (4)3分之x+5-2分之3x+2≥0

2025-05-18 09:01:27
推荐回答(3个)
回答(1):

(1)-3x<-15
x>(-15)÷(-3)
x>5

(2)2x+3>5
2x>5-3
2x>2
x>1

(3)2分之2+x≥3分之2x-1
两边同乘以6,得
3(2+x)≥2(2x-1)
6+3x≥4x-2
4x-3x≤6+2
x≤8

(4)3分之x+5-2分之3x+2≥0
两边同乘以6,得
2(x+5)-3(3x+2)≥0
2x+10-9x-6≥0
-7x≥-4
x≤4/7

回答(2):

(1)x>5
(2)x>1
(3)3(2+x)≥2(2x-1)
6+3x≥4x-2
x≤8
(4)2(x+5)-3(3x+2)≥0
2x+10-9x-6≥0
-7x≥-4
x≤4/7

满意请采纳,谢谢~

回答(3):

(1)-3x<-15

x>-15/-3
∴x>5

(2)2x+3>5

2x>5-3=2
x>1

(3)2分之2+x≥3分之2x-1

2分之2+x-3分之2x-1≥0

(2+x)乘以3-(2x-1)乘以2的差除以6≥0
(8-x)/6≥0
8-x≥0
x≤8

(4)3分之x+5-2分之3x+2≥0

[(x+5)乘以2-(3x+2)乘以3]/6≥0
(4-7x)/6≥0
4-7x≥0

-7x≥-4

x≤4/7