Question

当k为何值时,关于x的方程4x-3(x-3)=5x+3(k+6)的解

1.为负数?
2.小于-(1\2)?
3.不大于k的相反数?

Answer 1

4x-3(x-3)=5x+3(k+6)
4x-3x+9=5x+3k+18
4x=-9-3k
x=-(3k+9)/4

1.为负数
x<0
-(3k+9)/4<0
3k+9>0
k>-3

2.小于-(1\2)
-(3k+9)/4<-1/2
(3k+9)/4>1/2
3k+9>2
3k>-7
k>-7/3

3.不大于k的相反数
-(3k+9)/4≤-k
3k+9≥4k
k≤9

Answer 2

4x-3(x-3)=5x+3(k+6)
x+9=8k+18
x=8k+9
1)
x=8k+9<0
k<-9/8
2)
x=8k+9<-1/2
k<-19/16
3)x=8k+9≤-k
9k≤-9
k≤-1

Answer 3

4x-3x+9=5x+3k+18
x=(-3k-9)/4
(1)(-3k-9)/4<0
-3k-9<0
-3k<9
k>-3
(2)(-3k-9)/4<-1/2
(3k+9)/4>1/2
3k+9>2
k>-7/3
(3)(-3k-9)/4<=-k
-3k-9<=-4k
K<=9

Answer 4

4X=-3K-9
1.K<-3
2K<-7\3
3K<=9