1.x+y+z=21,x-y=1,2x+z-y=13.2.3x+2y+z=13,x+y+2z=7 ,2z+3y-z=12 3.x∶y=3∶2,y∶x=5∶4,2x+y+z
问题描述:
1.x+y+z=21,x-y=1,2x+z-y=13.2.3x+2y+z=13,x+y+2z=7 ,2z+3y-z=12 3.x∶y=3∶2,y∶x=5∶4,2x+y+z
3.x∶y=3∶2,y∶x=5∶4,2x+y+z=96
答
1.x=10,y=9,z=2
2.x=3,y=2,z=1
3.x=30,y=20,z=16.