已知x,y,m同时满足2x-3y=11-4m,3x+2y=21-5m,x+3y=20-7m,求m的值

来源:学生作业帮助网 编辑:作业帮 时间:2024/05/05 11:03:08
已知x,y,m同时满足2x-3y=11-4m,3x+2y=21-5m,x+3y=20-7m,求m的值

已知x,y,m同时满足2x-3y=11-4m,3x+2y=21-5m,x+3y=20-7m,求m的值
已知x,y,m同时满足2x-3y=11-4m,3x+2y=21-5m,x+3y=20-7m,求m的值

已知x,y,m同时满足2x-3y=11-4m,3x+2y=21-5m,x+3y=20-7m,求m的值
2x-3y=11-4m,----1式
3x+2y=21-5m,2式
x+3y=20-7m,3式
1+2:3x=31-11m
2-3:y=3m-5
31-11m+9m-15=60-21m
75-31=19m
44=19m

X=3,Y=1,m=2

1式加班加3式得X,代入2式得Y,再把X与Y代入1式知m=2

解这三元一次方程
2x-3y=11-4m
3x+2y=21-5m
x+3y=20-7m
m=2