Question

方程组4x+3m=2,8x-3y=m的解X.Y满足x大于y，则m的取值范围

Answer 1

m>10/19. 4x+3m=2得到x=(2-3m)/4 代入8x-3y=m得y=(4-7m)/3 有x>y知(2-3m)/4 >(4-7m)/3
得m>10/19

Answer 2

数学报纸上的题目吧 刚教过学生
先解出X=(2-3M)/4
因为4X=2-3m
8x=4-6m
3Y=M-8X=M-4+6M=7M-4
Y=(7M-4)/3
X＞Y
(2-3M)/4＞(7M-4)/3
解出M＜22/37

Answer 3

4x+3m=2 (1)
8x-3y=m (2)
from (1)
4x+3m=2
x= (2-3m)/4
from (2)
8x-3y=m
2(2-3m)-3y=m
3y = 4-7m
y =(4-7m)/3
x>y
(2-3m)/4 > (4-7m)/3
3(2-3m) > 4(4-7m)
6-9m >16 -28m
19m > 10
m> 10/19