解方程组:{x(x+y+z)=6 {y(x+y+z)=9 {z(x+y+z)=10

来源:学生作业帮助网 编辑:六六作业网 时间:2024/12/22 02:25:22
解方程组:{x(x+y+z)=6{y(x+y+z)=9{z(x+y+z)=10解方程组:{x(x+y+z)=6{y(x+y+z)=9{z(x+y+z)=10解方程组:{x(x+y+z)=6{y(x+y

解方程组:{x(x+y+z)=6 {y(x+y+z)=9 {z(x+y+z)=10
解方程组:{x(x+y+z)=6 {y(x+y+z)=9 {z(x+y+z)=10

解方程组:{x(x+y+z)=6 {y(x+y+z)=9 {z(x+y+z)=10
设x+y+z≠0

x(x+y+z)=6 (1)
y(x+y+z)=9 (2)
z(x+y+z)=10 (3)
(1)/(2)得:x/y=2/3
(3)/(1)得:z/x=5/3
(2)/(3)得:y/z=9/10
x=2/3y,z=10/9y
代入(1)得
y(2/3y+y+10/9y)=9
y=±9/5
当y=9/5时,x=6/5,z=2
当y=-9/5时,x=-6/5,z=-2