已知 2x-y-z=0 ,3x+4y-2z=0,问x:y:z=几

来源:学生作业帮助网 编辑:六六作业网 时间:2024/11/07 23:43:33
已知2x-y-z=0,3x+4y-2z=0,问x:y:z=几已知2x-y-z=0,3x+4y-2z=0,问x:y:z=几已知2x-y-z=0,3x+4y-2z=0,问x:y:z=几2x-y-z=0,(

已知 2x-y-z=0 ,3x+4y-2z=0,问x:y:z=几
已知 2x-y-z=0 ,3x+4y-2z=0,问x:y:z=几

已知 2x-y-z=0 ,3x+4y-2z=0,问x:y:z=几
2x-y-z=0,(1)
3x+4y-2z=0,(2)
(1)式乘以2-(2)得
4x-2y-2z-(3x+4y-2z)=0
即是x-6y=0 ,x=6y 带入(1)得 12y-y-z=0 得z=11y
x:y:z=6:1:11

令Z=1则
2X-Y=1
3X+4Y=2
解得X=6/11,Y=1/11
x:y:z=6/11:1/11:1=6:1:11

2x-y-z=0 -------(1)
3x+4y-2z=0 ------(2)
4*(1)+(2),得:x=(6/11)z
3*(1)-2*(2),得:y=(1/11)z
所以:
x:y:z=(6/11):(1/11):1=6:1:11

(1)2X-Y-Z=0
(2)3x+4y-2z=0
根据(1)得z=2X-Y带入(2)得3X+4Y-2(2X+Y)=0,6Y-X=0,X=6Y
再带入(1)12Y-Y-Z=0,Z=11Y
所以X:Y:Z=6:1:11